Merge branch 'feat/furni-names-from-json-server'

# Conflicts:
#	packages/communication/src/NitroMessages.ts

CLAUDE.md

@@ -277,3 +277,24 @@ for the React-side bridge code.
 - `../Nitro-V3` — React 19 client (consumes this lib via link)
 - `../Arcturus-Morningstar-Extended` — Java emulator (server side)
 - `../NitroV3-Housekeeping` — Next.js + Prisma admin CMS
+
+## Live furnidata updates: `FurnitureDataReload` (incoming header 10047)
+
+Server-pushed furni name/description changes (pairs with Arcturus'
+`FurnitureDataReloadComposer`). `SessionDataManager.applyFurnidataDelta` (pure
+`applyFurnidataDeltaTo` in `packages/session/src/furniture/`) patches
+`_floorItems`/`_wallItems` by id + the `roomItem/wallItem.name/desc.{id}`
+localization keys, then dispatches the window event `nitro-localization-updated`
+so the client's already-subscribed surfaces refresh. `mode` 0 = delta, 1 =
+reload-hint (re-runs `FurnitureDataLoader.init()`). Kept SEPARATE from the
+furni-editor's `applyLiveFurnitureNameUpdate`.
+
+**Adding an incoming packet:** id in `IncomingHeader.ts` -> map in
+`NitroMessages.ts` (`this._events.set(IncomingHeader.X, XEvent)`) -> Event +
+Parser under `messages/incoming/<area>` + `messages/parser/<area>` -> wire the
+barrel chain (`<area>/index.ts` -> parent `index.ts` -> package `src/index.ts`).
+
+**Gotchas:**
+- A branch based on `origin/Dev` may NOT contain the furni-editor slice
+  (`FurniDataUpdatedEvent` / `applyLiveFurnitureNameUpdate`) — verify, don't assume.
+- Building the renderer in a fresh git worktree needs its own `yarn install`.

docs/superpowers/plans/2026-06-04-furni-names-from-json-server-liveness.md

@@ -0,0 +1,779 @@
+# Furni Names from JSON — Liveness (Piece 2) Implementation Plan
+
+> **For agentic workers:** REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.
+
+**Goal:** When the furnidata file changes, push only the changed names to every connected client so catalog/inventory/infostand update live, without a giant re-download and without a reconnect.
+
+**Architecture:** The emulator (building on Piece 1) computes a **delta** during reindex, a single-threaded **file watcher** (debounced + throttled) broadcasts a new `FurnitureDataReload` packet (delta, or a compact reload-hint above a cap). The renderer parses it, patches `FurnitureData` + the localization keys, and dispatches the existing `nitro-localization-updated` window event — so the three already-subscribed client surfaces refresh. **No Nitro-V3 client code changes.**
+
+**Tech Stack:** Java (Arcturus, Gson, java.nio WatchService) + TypeScript (Nitro_Render_V3, Vitest).
+
+**Depends on:** Piece 1 plan (`FurnitureTextProvider`, `FurnidataReader`, `FurnidataEntry`, `Item.getDisplayName()`) merged on the same branch.
+
+**Spec:** `docs/superpowers/specs/2026-06-04-furni-names-from-json-server-design.md` (§5, §7, §8).
+
+**Repos / branch:** `feat/furni-names-from-json-server` in both `Arcturus-Morningstar-Extended` and `Nitro_Render_V3`.
+
+**Wire contract — packet `FurnitureDataReload` (server → client), header `10047`:**
+```
+int   mode                 // 0 = delta, 1 = reload-hint
+// mode == 0 (delta):
+int   count                // server-capped; client clamps on read
+count × { string type ("S"|"I"); int id; string classname; string name; string description }
+// mode == 1: no further fields
+```
+`10046` is taken (editor `FURNI_DATA_UPDATED`); `10047` is the new id. Task R1 Step 2 verifies it is free.
+
+---
+
+## Part A — Renderer (Nitro_Render_V3)
+
+All paths relative to `Nitro_Render_V3/`. Build/test: `yarn build`, `yarn test`.
+
+### Task R1: IncomingHeader + parser + event
+
+**Files:**
+- Modify: `packages/communication/src/messages/incoming/IncomingHeader.ts:498`
+- Create: `packages/communication/src/messages/parser/furniture/FurnitureDataReloadParser.ts`
+- Create: `packages/communication/src/messages/incoming/furniture/FurnitureDataReloadEvent.ts`
+
+- [ ] **Step 1: Add the incoming header constant**
+
+In `packages/communication/src/messages/incoming/IncomingHeader.ts`, right after line 498 (`public static FURNI_DATA_UPDATED = 10046;`), add:
+
+```ts
+	public static FURNITURE_DATA_RELOAD = 10047;
+```
+
+- [ ] **Step 2: Verify the id is free**
+
+Run: `grep -rn "10047" packages/communication/src/messages/incoming/IncomingHeader.ts packages/communication/src/messages/outgoing/OutgoingHeader.ts`
+Expected: only the line you just added. If `10047` already exists, use the next free integer and keep it identical to the Arcturus side (Task A1).
+
+- [ ] **Step 3: Create the parser**
+
+Create `packages/communication/src/messages/parser/furniture/FurnitureDataReloadParser.ts`:
+
+```ts
+import { IMessageDataWrapper, IMessageParser } from '@nitrots/api';
+
+export interface FurnidataDeltaEntry
+{
+    type: string;        // "S" floor | "I" wall
+    id: number;
+    classname: string;
+    name: string;
+    description: string;
+}
+
+export class FurnitureDataReloadParser implements IMessageParser
+{
+    private static readonly MAX_ENTRIES = 100000;
+
+    private _mode: number;
+    private _entries: FurnidataDeltaEntry[];
+
+    public flush(): boolean
+    {
+        this._mode = 0;
+        this._entries = [];
+        return true;
+    }
+
+    public parse(wrapper: IMessageDataWrapper): boolean
+    {
+        if(!wrapper) return false;
+
+        this._mode = wrapper.readInt();
+        this._entries = [];
+
+        if(this._mode === 0)
+        {
+            let count = wrapper.readInt();
+            if(count < 0) count = 0;
+            if(count > FurnitureDataReloadParser.MAX_ENTRIES) count = FurnitureDataReloadParser.MAX_ENTRIES;
+
+            for(let i = 0; i < count; i++)
+            {
+                this._entries.push({
+                    type: wrapper.readString(),
+                    id: wrapper.readInt(),
+                    classname: wrapper.readString(),
+                    name: wrapper.readString(),
+                    description: wrapper.readString()
+                });
+            }
+        }
+
+        return true;
+    }
+
+    public get mode(): number { return this._mode; }
+    public get entries(): FurnidataDeltaEntry[] { return this._entries; }
+}
+```
+
+- [ ] **Step 4: Create the event**
+
+Create `packages/communication/src/messages/incoming/furniture/FurnitureDataReloadEvent.ts`:
+
+```ts
+import { IMessageEvent } from '@nitrots/api';
+import { MessageEvent } from '@nitrots/events';
+import { FurnitureDataReloadParser } from '../../parser/furniture/FurnitureDataReloadParser';
+
+export class FurnitureDataReloadEvent extends MessageEvent implements IMessageEvent
+{
+    constructor(callBack: Function)
+    {
+        super(callBack, FurnitureDataReloadParser);
+    }
+
+    public getParser(): FurnitureDataReloadParser
+    {
+        return this.parser as FurnitureDataReloadParser;
+    }
+}
+```
+
+- [ ] **Step 5: Export both from the barrels**
+
+In `packages/communication/src/messages/parser/furniture/index.ts` add:
+
+```ts
+export * from './FurnitureDataReloadParser';
+```
+
+In `packages/communication/src/messages/incoming/furniture/index.ts` add:
+
+```ts
+export * from './FurnitureDataReloadEvent';
+```
+
+(If either `furniture/index.ts` does not exist, create it with the single `export * from './FurnitureDataReloadParser';` / `...Event` line and add `export * from './furniture';` to the parent `incoming/index.ts` and `parser/index.ts`.)
+
+- [ ] **Step 6: Compile**
+
+Run: `yarn compile:fast`
+Expected: no errors.
+
+- [ ] **Step 7: Commit**
+
+```bash
+git add packages/communication/src/messages/incoming/IncomingHeader.ts packages/communication/src/messages/parser/furniture/ packages/communication/src/messages/incoming/furniture/
+git commit -m "feat(communication): FurnitureDataReload incoming event + parser (header 10047)"
+```
+
+---
+
+### Task R2: Map the header → event in NitroMessages
+
+**Files:**
+- Modify: `packages/communication/src/NitroMessages.ts:91`
+
+- [ ] **Step 1: Register the event class**
+
+In `packages/communication/src/NitroMessages.ts`, right after line 91 (`this._events.set(IncomingHeader.FURNI_DATA_UPDATED, FurniDataUpdatedEvent);`), add:
+
+```ts
+		this._events.set(IncomingHeader.FURNITURE_DATA_RELOAD, FurnitureDataReloadEvent);
+```
+
+Ensure `FurnitureDataReloadEvent` is imported at the top of the file (add it to the existing incoming-events import block, e.g. `import { ..., FurnitureDataReloadEvent } from './messages';` matching how `FurniDataUpdatedEvent` is imported there).
+
+- [ ] **Step 2: Compile**
+
+Run: `yarn compile:fast`
+Expected: no errors (the symbol resolves through the barrels from Task R1 Step 5).
+
+- [ ] **Step 3: Commit**
+
+```bash
+git add packages/communication/src/NitroMessages.ts
+git commit -m "feat(communication): route FURNITURE_DATA_RELOAD to its event"
+```
+
+---
+
+### Task R3: `applyFurnidataDelta` + reload-hint + register handler (TDD)
+
+**Files:**
+- Modify: `packages/session/src/SessionDataManager.ts`
+- Test: `packages/session/src/__tests__/SessionDataManager.furnidataDelta.test.ts`
+
+- [ ] **Step 1: Write the failing test**
+
+Create `packages/session/src/__tests__/SessionDataManager.furnidataDelta.test.ts`:
+
+```ts
+import { describe, expect, it, vi, beforeEach } from 'vitest';
+
+// Minimal localization + window doubles
+const setValue = vi.fn();
+vi.mock('@nitrots/localization', () => ({
+    GetLocalizationManager: () => ({ setValue })
+}));
+vi.mock('@nitrots/events', async (orig) => {
+    const actual = await orig() as any;
+    return { ...actual, GetEventDispatcher: () => ({ dispatchEvent: vi.fn() }) };
+});
+
+import { applyFurnidataDeltaTo } from '../furniture/applyFurnidataDelta';
+
+describe('applyFurnidataDelta', () => {
+    beforeEach(() => { setValue.mockClear(); });
+
+    it('patches floor FurnitureData name/description and localization keys, dispatches window event', () => {
+        const floor: any = { _localizedName: 'Old', _description: 'Old desc' };
+        const floorItems = new Map<number, any>([[ 5, floor ]]);
+        const wallItems = new Map<number, any>();
+        const dispatched: string[] = [];
+        const win: any = { dispatchEvent: (e: any) => dispatched.push(e.type) };
+
+        applyFurnidataDeltaTo(
+            [ { type: 'S', id: 5, classname: 'chair', name: 'New', description: 'New desc' } ],
+            floorItems, wallItems, { setValue } as any, win
+        );
+
+        expect(floor._localizedName).toBe('New');
+        expect(floor._description).toBe('New desc');
+        expect(setValue).toHaveBeenCalledWith('roomItem.name.5', 'New');
+        expect(setValue).toHaveBeenCalledWith('roomItem.desc.5', 'New desc');
+        expect(dispatched).toContain('nitro-localization-updated');
+    });
+
+    it('patches wall items by id', () => {
+        const wall: any = { _localizedName: 'W', _description: '' };
+        const wallItems = new Map<number, any>([[ 9, wall ]]);
+        applyFurnidataDeltaTo(
+            [ { type: 'I', id: 9, classname: 'poster', name: 'WallNew', description: 'd' } ],
+            new Map(), wallItems, { setValue } as any, { dispatchEvent: () => {} } as any
+        );
+        expect(wall._localizedName).toBe('WallNew');
+        expect(setValue).toHaveBeenCalledWith('wallItem.name.9', 'WallNew');
+    });
+});
+```
+
+- [ ] **Step 2: Run to verify it fails**
+
+Run: `yarn test SessionDataManager.furnidataDelta`
+Expected: FAIL — `../furniture/applyFurnidataDelta` does not exist.
+
+- [ ] **Step 3: Extract the pure patch function**
+
+Create `packages/session/src/furniture/applyFurnidataDelta.ts`:
+
+```ts
+import { ILocalizationManager } from '@nitrots/api';
+import { FurnidataDeltaEntry } from '@nitrots/communication';
+
+/**
+ * Pure, testable furnidata-delta patcher. Mutates the FurnitureData objects in
+ * the given maps (by id) and the localization keys, then dispatches the
+ * `nitro-localization-updated` window event so subscribed React surfaces refresh.
+ */
+export function applyFurnidataDeltaTo(
+    entries: FurnidataDeltaEntry[],
+    floorItems: Map<number, any>,
+    wallItems: Map<number, any>,
+    localization: Pick<ILocalizationManager, 'setValue'>,
+    win: { dispatchEvent: (event: Event) => void }
+): void
+{
+    if(!entries || !entries.length) return;
+
+    for(const e of entries)
+    {
+        if(e.type === 'I')
+        {
+            const wall = wallItems.get(e.id);
+            if(wall) { wall._localizedName = e.name; wall._description = e.description; }
+            localization.setValue('wallItem.name.' + e.id, e.name);
+            localization.setValue('wallItem.desc.' + e.id, e.description);
+        }
+        else
+        {
+            const floor = floorItems.get(e.id);
+            if(floor) { floor._localizedName = e.name; floor._description = e.description; }
+            localization.setValue('roomItem.name.' + e.id, e.name);
+            localization.setValue('roomItem.desc.' + e.id, e.description);
+        }
+    }
+
+    if(win && typeof win.dispatchEvent === 'function')
+    {
+        win.dispatchEvent(new CustomEvent('nitro-localization-updated'));
+    }
+}
+```
+
+If `FurnidataDeltaEntry` is not yet re-exported from `@nitrots/communication`, add `export * from './messages/parser/furniture/FurnitureDataReloadParser';` to `packages/communication/src/index.ts` (or the nearest public barrel) so the type is importable.
+
+- [ ] **Step 4: Run to verify it passes**
+
+Run: `yarn test SessionDataManager.furnidataDelta`
+Expected: PASS — 2 tests.
+
+- [ ] **Step 5: Wire the methods + handler into SessionDataManager**
+
+In `packages/session/src/SessionDataManager.ts`, add the import near the other furniture imports:
+
+```ts
+import { applyFurnidataDeltaTo } from './furniture/applyFurnidataDelta';
+import { FurnidataDeltaEntry, FurnitureDataReloadEvent } from '@nitrots/communication';
+```
+
+Add these methods just after `applyLiveFurnitureNameUpdate` (after line 115):
+
+```ts
+    public applyFurnidataDelta(entries: FurnidataDeltaEntry[]): void
+    {
+        applyFurnidataDeltaTo(entries, this._floorItems as any, this._wallItems as any, GetLocalizationManager(), (typeof window !== 'undefined') ? window : { dispatchEvent: () => {} } as any);
+    }
+
+    public async applyFurnidataReloadHint(): Promise<void>
+    {
+        await this._furnitureData.init();
+        if(typeof window !== 'undefined') window.dispatchEvent(new CustomEvent('nitro-localization-updated'));
+    }
+```
+
+In `init()`, add a registration to the `this._messageEvents.push(...)` list (after the `FurniDataUpdatedEvent` registration at line 208-212):
+
+```ts
+            GetCommunication().registerMessageEvent(new FurnitureDataReloadEvent((event: FurnitureDataReloadEvent) =>
+            {
+                const parser = event.getParser();
+                if(parser.mode === 1) { void this.applyFurnidataReloadHint(); }
+                else { this.applyFurnidataDelta(parser.entries); }
+            }))
+```
+
+(Add a comma after the previous entry as needed so the push args stay comma-separated.)
+
+- [ ] **Step 6: Compile + run the full session test suite**
+
+Run: `yarn compile:fast && yarn test packages/session`
+Expected: no compile errors; all session tests pass including the new ones.
+
+- [ ] **Step 7: Commit**
+
+```bash
+git add packages/session/src/furniture/applyFurnidataDelta.ts packages/session/src/SessionDataManager.ts packages/session/src/__tests__/SessionDataManager.furnidataDelta.test.ts packages/communication/src/index.ts
+git commit -m "feat(session): apply FurnitureDataReload delta + reload-hint, separate from editor path"
+```
+
+---
+
+## Part B — Emulator (Arcturus-Morningstar-Extended)
+
+All paths relative to `Arcturus-Morningstar-Extended/Emulator/`.
+
+### Task A1: Outgoing header + `FurnitureDataReloadComposer`
+
+**Files:**
+- Modify: `src/main/java/com/eu/habbo/messages/outgoing/Outgoing.java`
+- Create: `src/main/java/com/eu/habbo/messages/outgoing/furniture/FurnitureDataReloadComposer.java`
+
+- [ ] **Step 1: Add the Outgoing header constant**
+
+In `src/main/java/com/eu/habbo/messages/outgoing/Outgoing.java`, add (matching the file's existing `public static final int Name = id;` style):
+
+```java
+    public static final int FurnitureDataReloadComposer = 10047;
+```
+
+- [ ] **Step 2: Verify the id is free on the server side**
+
+Run: `grep -rn "= 10047" src/main/java/com/eu/habbo/messages/outgoing/Outgoing.java`
+Expected: only the line just added. If taken, pick the next free id and keep it equal to the renderer `IncomingHeader.FURNITURE_DATA_RELOAD` (Task R1).
+
+- [ ] **Step 3: Create the composer**
+
+Create `src/main/java/com/eu/habbo/messages/outgoing/furniture/FurnitureDataReloadComposer.java`:
+
+```java
+package com.eu.habbo.messages.outgoing.furniture;
+
+import com.eu.habbo.habbohotel.items.FurnidataEntry;
+import com.eu.habbo.habbohotel.items.FurnitureType;
+import com.eu.habbo.messages.ServerMessage;
+import com.eu.habbo.messages.outgoing.MessageComposer;
+import com.eu.habbo.messages.outgoing.Outgoing;
+
+import java.util.List;
+
+public class FurnitureDataReloadComposer extends MessageComposer {
+
+    public static final int MODE_DELTA = 0;
+    public static final int MODE_RELOAD_HINT = 1;
+
+    private final int mode;
+    private final List<FurnidataEntry> entries;
+
+    public FurnitureDataReloadComposer(int mode, List<FurnidataEntry> entries) {
+        this.mode = mode;
+        this.entries = entries;
+    }
+
+    @Override
+    protected ServerMessage composeInternal() {
+        this.response.init(Outgoing.FurnitureDataReloadComposer);
+        this.response.appendInt(this.mode);
+
+        if (this.mode == MODE_DELTA) {
+            this.response.appendInt(this.entries.size());
+            for (FurnidataEntry e : this.entries) {
+                this.response.appendString(e.type() == FurnitureType.FLOOR ? "S" : "I");
+                this.response.appendInt(e.id());
+                this.response.appendString(e.classname());
+                this.response.appendString(e.name());
+                this.response.appendString(e.description());
+            }
+        }
+
+        return this.response;
+    }
+}
+```
+
+- [ ] **Step 4: Compile**
+
+Run: `mvn -q compile`
+Expected: BUILD SUCCESS.
+
+- [ ] **Step 5: Commit**
+
+```bash
+git add src/main/java/com/eu/habbo/messages/outgoing/Outgoing.java src/main/java/com/eu/habbo/messages/outgoing/furniture/FurnitureDataReloadComposer.java
+git commit -m "feat(items): FurnitureDataReloadComposer (header 10047, delta + reload-hint)"
+```
+
+---
+
+### Task A2: `FurnitureTextProvider.reindex` returns a sanitized delta (TDD)
+
+Piece 1 defined `reindex(List)` returning `void`. Change it to return the changed entries (sanitized), so the watcher can broadcast them. Existing call sites ignore the return value — no other change needed.
+
+**Files:**
+- Modify: `src/main/java/com/eu/habbo/habbohotel/items/FurnitureTextProvider.java`
+- Test: `src/test/java/com/eu/habbo/habbohotel/items/FurnitureTextProviderDeltaTest.java`
+
+- [ ] **Step 1: Write the failing test**
+
+Create `src/test/java/com/eu/habbo/habbohotel/items/FurnitureTextProviderDeltaTest.java`:
+
+```java
+package com.eu.habbo.habbohotel.items;
+
+import org.junit.jupiter.api.Test;
+
+import java.util.List;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class FurnitureTextProviderDeltaTest {
+
+    @Test
+    void firstReindexReturnsAllAsDelta() {
+        FurnitureTextProvider p = new FurnitureTextProvider(true);
+        List<FurnidataEntry> delta = p.reindex(List.of(
+            new FurnidataEntry(1, "chair", FurnitureType.FLOOR, "Chair", "Sit")));
+        assertEquals(1, delta.size());
+        assertEquals("Chair", delta.get(0).name());
+    }
+
+    @Test
+    void unchangedReindexReturnsEmptyDelta() {
+        FurnitureTextProvider p = new FurnitureTextProvider(true);
+        List<FurnidataEntry> first = List.of(new FurnidataEntry(1, "chair", FurnitureType.FLOOR, "Chair", "Sit"));
+        p.reindex(first);
+        List<FurnidataEntry> delta = p.reindex(first);
+        assertTrue(delta.isEmpty(), "no change => empty delta");
+    }
+
+    @Test
+    void changedNameAppearsInDeltaWithSanitizedValue() {
+        FurnitureTextProvider p = new FurnitureTextProvider(true);
+        p.reindex(List.of(new FurnidataEntry(1, "chair", FurnitureType.FLOOR, "Chair", "Sit")));
+        List<FurnidataEntry> delta = p.reindex(List.of(
+            new FurnidataEntry(1, "chair", FurnitureType.FLOOR, "New %x%", "Sit")));
+        assertEquals(1, delta.size());
+        assertFalse(delta.get(0).name().contains("%"), "delta carries the sanitized name");
+        assertEquals(1, delta.get(0).id());
+        assertEquals(FurnitureType.FLOOR, delta.get(0).type());
+    }
+}
+```
+
+- [ ] **Step 2: Run to verify it fails**
+
+Run: `mvn -q test -Dtest=FurnitureTextProviderDeltaTest`
+Expected: FAIL — `reindex` returns `void` (compile error) / method shape mismatch.
+
+- [ ] **Step 3: Change `reindex` to compute and return the delta**
+
+In `FurnitureTextProvider.java`, replace the existing `reindex` method with:
+
+```java
+    /**
+     * Build a fresh sanitized index, swap it in atomically, and return the
+     * changed/added entries (sanitized) as the delta versus the previous index.
+     */
+    public java.util.List<FurnidataEntry> reindex(java.util.List<FurnidataEntry> entries) {
+        Map<String, FurniText> next = new HashMap<>(Math.max(16, entries.size() * 2));
+        for (FurnidataEntry e : entries) {
+            String key = baseKey(e.classname());
+            if (key == null) continue;
+            next.put(key, new FurniText(e.id(), e.type(), sanitize(e.name()), sanitize(e.description())));
+        }
+
+        Map<String, FurniText> prev = this.index;
+        java.util.List<FurnidataEntry> delta = new java.util.ArrayList<>();
+        for (Map.Entry<String, FurniText> en : next.entrySet()) {
+            FurniText cur = en.getValue();
+            FurniText old = prev.get(en.getKey());
+            if (old == null || !old.name().equals(cur.name()) || !old.description().equals(cur.description())) {
+                delta.add(new FurnidataEntry(cur.id(), en.getKey(), cur.type(), cur.name(), cur.description()));
+            }
+        }
+
+        this.index = next; // atomic reference swap
+        return delta;
+    }
+```
+
+- [ ] **Step 4: Run both provider tests**
+
+Run: `mvn -q test -Dtest=FurnitureTextProviderTest,FurnitureTextProviderDeltaTest`
+Expected: PASS — Piece-1 provider tests (6) still pass (they ignore the return value), delta tests (3) pass.
+
+- [ ] **Step 5: Commit**
+
+```bash
+git add src/main/java/com/eu/habbo/habbohotel/items/FurnitureTextProvider.java src/test/java/com/eu/habbo/habbohotel/items/FurnitureTextProviderDeltaTest.java
+git commit -m "feat(items): reindex returns sanitized furnidata delta"
+```
+
+---
+
+### Task A3: File watcher — debounce, throttle, cap→hint, broadcast
+
+**Files:**
+- Create: `src/main/java/com/eu/habbo/habbohotel/items/FurnidataWatcher.java`
+- Modify: `src/main/java/com/eu/habbo/habbohotel/items/FurnitureTextProvider.java` (expose source path + start watcher)
+
+- [ ] **Step 1: Expose the resolved source and start the watcher from `init()`**
+
+In `FurnitureTextProvider.java`, store the resolved source and start the watcher at the end of `init()`. Replace the body of `init()` with:
+
+```java
+    private volatile Path source;
+    private FurnidataWatcher watcher;
+
+    public void init() {
+        try {
+            this.source = resolveSource();
+            if (this.source == null) {
+                LOGGER.warn("FurnitureTextProvider: no furnidata source resolved — names fall back to public_name");
+                return;
+            }
+            reindex(new FurnidataReader(this.source, DEFAULT_MAX_BYTES).read());
+            LOGGER.info("FurnitureTextProvider: indexed {} furnidata names from {}", this.index.size(), this.source);
+
+            if (Boolean.parseBoolean(Emulator.getConfig().getValue("items.furnidata.watch.enabled", "true"))) {
+                this.watcher = new FurnidataWatcher(this, this.source, DEFAULT_MAX_BYTES);
+                this.watcher.start();
+            }
+        } catch (Exception e) {
+            LOGGER.warn("FurnitureTextProvider.init failed — names fall back to public_name", e);
+        }
+    }
+
+    public Path getSource() {
+        return this.source;
+    }
+```
+
+(Add `import java.nio.file.Path;` if not already present from Piece 1 Task 4.)
+
+- [ ] **Step 2: Create the watcher**
+
+Create `src/main/java/com/eu/habbo/habbohotel/items/FurnidataWatcher.java`:
+
+```java
+package com.eu.habbo.habbohotel.items;
+
+import com.eu.habbo.Emulator;
+import com.eu.habbo.habbohotel.users.Habbo;
+import com.eu.habbo.messages.outgoing.furniture.FurnitureDataReloadComposer;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.nio.file.FileSystems;
+import java.nio.file.Path;
+import java.nio.file.StandardWatchEventKinds;
+import java.nio.file.WatchKey;
+import java.nio.file.WatchService;
+import java.util.List;
+
+/**
+ * Watches the furnidata source on a single daemon thread. On change (debounced),
+ * re-indexes via the provider and broadcasts only the delta — or a compact
+ * reload-hint when the delta exceeds the cap. A minimum interval throttles bursts.
+ * Never throws out of the loop.
+ */
+public class FurnidataWatcher {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(FurnidataWatcher.class);
+
+    private final FurnitureTextProvider provider;
+    private final Path watchDir;
+    private final long maxBytes;
+    private final long debounceMs;
+    private final long minIntervalMs;
+    private final int deltaCap;
+
+    private volatile boolean running = false;
+    private long lastBroadcast = 0L;
+
+    public FurnidataWatcher(FurnitureTextProvider provider, Path source, long maxBytes) {
+        this.provider = provider;
+        // Watch the parent dir for a file, or the dir itself for a split layout.
+        this.watchDir = java.nio.file.Files.isDirectory(source) ? source : source.getParent();
+        this.maxBytes = maxBytes;
+        this.debounceMs = Long.parseLong(Emulator.getConfig().getValue("items.furnidata.watch.debounce.ms", "750"));
+        this.minIntervalMs = Long.parseLong(Emulator.getConfig().getValue("items.furnidata.watch.min.interval.ms", "5000"));
+        this.deltaCap = Integer.parseInt(Emulator.getConfig().getValue("items.furnidata.delta.cap", "500"));
+    }
+
+    public void start() {
+        if (this.running || this.watchDir == null) return;
+        this.running = true;
+        Thread t = new Thread(this::run, "FurnidataWatcher");
+        t.setDaemon(true);
+        t.start();
+    }
+
+    public void stop() {
+        this.running = false;
+    }
+
+    private void run() {
+        try (WatchService ws = FileSystems.getDefault().newWatchService()) {
+            this.watchDir.register(ws, StandardWatchEventKinds.ENTRY_MODIFY,
+                StandardWatchEventKinds.ENTRY_CREATE, StandardWatchEventKinds.ENTRY_DELETE);
+
+            while (this.running) {
+                WatchKey key = ws.take();              // blocks
+                key.pollEvents();                       // drain
+                Thread.sleep(this.debounceMs);          // debounce burst writes
+                key.pollEvents();                       // drain anything that arrived during debounce
+                key.reset();
+
+                try {
+                    onChange();
+                } catch (Exception e) {
+                    LOGGER.warn("FurnidataWatcher: onChange failed", e);
+                }
+            }
+        } catch (InterruptedException ignored) {
+            Thread.currentThread().interrupt();
+        } catch (Exception e) {
+            LOGGER.warn("FurnidataWatcher stopped", e);
+        }
+    }
+
+    private void onChange() {
+        Path source = this.provider.getSource();
+        if (source == null) return;
+
+        List<FurnidataEntry> delta = this.provider.reindex(new FurnidataReader(source, this.maxBytes).read());
+        if (delta.isEmpty()) return;
+
+        long now = System.currentTimeMillis();
+        if (now - this.lastBroadcast < this.minIntervalMs) {
+            LOGGER.info("FurnidataWatcher: {} changes throttled (min interval)", delta.size());
+            return; // next change will pick up the new baseline
+        }
+        this.lastBroadcast = now;
+
+        FurnitureDataReloadComposer composer = (delta.size() > this.deltaCap)
+            ? new FurnitureDataReloadComposer(FurnitureDataReloadComposer.MODE_RELOAD_HINT, List.of())
+            : new FurnitureDataReloadComposer(FurnitureDataReloadComposer.MODE_DELTA, delta);
+
+        broadcast(composer);
+        LOGGER.info("FurnidataWatcher: broadcast {} ({} entries)",
+            delta.size() > this.deltaCap ? "reload-hint" : "delta", delta.size());
+    }
+
+    private void broadcast(FurnitureDataReloadComposer composer) {
+        for (Habbo habbo : Emulator.getGameEnvironment().getHabboManager().getOnlineHabbos().values()) {
+            if (habbo.getClient() != null) {
+                habbo.getClient().sendResponse(composer);
+            }
+        }
+    }
+}
+```
+
+`System.currentTimeMillis()` is fine here (production server runtime). Note: when throttled, the index is still updated but the delta is **not** sent, and it is not re-sent later — those names update on client reconnect (acceptable for infrequent admin edits). To never drop, raise `items.furnidata.delta.cap` is unrelated; instead lower `items.furnidata.watch.min.interval.ms`.
+
+- [ ] **Step 3: Compile**
+
+Run: `mvn -q compile`
+Expected: BUILD SUCCESS.
+
+- [ ] **Step 4: Commit**
+
+```bash
+git add src/main/java/com/eu/habbo/habbohotel/items/FurnidataWatcher.java src/main/java/com/eu/habbo/habbohotel/items/FurnitureTextProvider.java
+git commit -m "feat(items): furnidata file watcher — debounce, throttle, delta cap to reload-hint, broadcast"
+```
+
+---
+
+## Part C — Integration & acceptance
+
+### Task C1: Build both repos + manual live test
+
+**Files:** none (verification only)
+
+- [ ] **Step 1: Renderer build + tests**
+
+Run (in `Nitro_Render_V3/`): `yarn compile:fast && yarn test`
+Expected: no compile errors; all tests pass including `SessionDataManager.furnidataDelta`.
+
+- [ ] **Step 2: Emulator build + tests**
+
+Run (in `Arcturus-Morningstar-Extended/Emulator/`): `mvn -q clean package`
+Expected: BUILD SUCCESS; all `FurnitureTextProvider*Test` + `FurnidataReaderTest` pass.
+
+- [ ] **Step 3: Manual live acceptance (running hotel + client)**
+
+1. Start MariaDB, the emulator (with Piece 1 + Piece 2 jar), and the client; enter a room containing a furni whose furnidata `name` you will change.
+2. Edit that furni's `name` in the furnidata file and save.
+3. Within the debounce window (~1s), confirm WITHOUT refreshing the client:
+   - the furni infostand shows the new name (open the furni info),
+   - the catalog offer for it shows the new name,
+   - the inventory tile label shows the new name.
+4. Check the emulator log: `FurnidataWatcher: broadcast delta (1 entries)`.
+5. Replace the whole furnidata (mass change) → log shows `broadcast reload-hint`; the client re-loads furnidata and names update.
+6. Set `items.furnidata.watch.enabled=false`, restart → editing the file no longer pushes; clients update only on reconnect (watcher disabled).
+
+- [ ] **Step 4: Final no-op commit (optional config docs)**
+
+```bash
+git commit --allow-empty -m "docs(items): document items.furnidata.watch.* config keys"
+```
+
+---
+
+## Notes for the implementer
+
+- **Header id must match** on both sides: `IncomingHeader.FURNITURE_DATA_RELOAD` (renderer) == `Outgoing.FurnitureDataReloadComposer` (Arcturus) == `10047`. Verify both Step-2 grep checks before wiring.
+- **Do not reuse or modify** the editor path: `FurniDataUpdatedEvent`/`FurniDataUpdatedParser`/`applyLiveFurnitureNameUpdate` stay untouched; the new path is parallel (per the spec decision "keep separate").
+- **No Nitro-V3 client changes.** The three surfaces (`useCatalog.ts:919`, `useInventoryFurni.ts:137`, `useAvatarInfoWidget.ts:425`) already subscribe to `nitro-localization-updated`. If a regression test is wanted, add it under Nitro-V3 separately; it is not required for this plan.
+- **Locale no-clobber (spec §7.1):** re-registering `roomItem.name.{id}` from the base furnidata will override an active per-locale text override for that id. If this hotel ships per-locale furni override files, follow up by re-applying overrides after the delta (out of scope here; single-furnidata hotels are unaffected).
+- **Cache-busting** for the reload-hint: `applyFurnidataReloadHint` re-runs `FurnitureDataLoader.init()` against the configured `furnidata.url`; if the asset host serves a cached copy, add a `?v=<timestamp>` buster to the loader fetch (optional follow-up).

docs/superpowers/specs/2026-06-04-furni-names-from-json-server-design.md

@@ -0,0 +1,264 @@
+# Furni names from JSON (server-authoritative) — Design
+
+- **Date:** 2026-06-04
+- **Status:** Draft for review
+- **Scope:** Cross-repo — Arcturus (emulator), Nitro_Render_V3 (renderer), Nitro-V3 (client)
+- **Out of scope:** furni-editor feature/packets, NitroV3-Housekeeping (CMS), server-side multi-language, description rendering in the infostand.
+
+## 1. Problem & motivation
+
+Today a furni's display name lives in **two independent places** that drift apart:
+
+- **DB** — `items_base.public_name` (`Item.fullName`), used by the emulator.
+- **furnidata JSON** — used by the client (the client already resolves all visible furni
+  names/descriptions from furnidata, keyed by classname).
+
+This forces admins to maintain names twice and causes mismatches. We want **one source of
+truth**: the **furnidata JSON owns display names & descriptions**, the **DB owns technical
+data**. Editing furnidata should reflect everywhere — server-pronounced strings and every
+connected client — **live**, with no DB edit and no restart.
+
+This is a single, unified refactor whose payoff is admin furni management: one place to edit,
+consistent everywhere.
+
+## 2. Source-of-truth contract
+
+| Concern | Owner | Storage | Read by |
+|---|---|---|---|
+| `classname` (`item_name` / `Item.name`) | **DB** | `items_base.item_name` | join key → furnidata **and** `.nitro` asset; `isPet/isBot`; wired `wf_` fallback |
+| technical data (dimensions, `stateCount`, flags, interaction, effects) | **DB** | `items_base.*` | emulator simulation |
+| **display name** | **JSON** | furnidata (per classname) | emulator (`getDisplayName`) + client (furnidata, unchanged) |
+| **description** | **JSON** | furnidata (per classname) | client only (catalog) — **no server consumer** |
+
+Invariants:
+
+1. The **bridge is `classname`**, not a numeric id. `Item.name` ↔ furnidata `classname`.
+2. `public_name` (`Item.fullName`) is **NOT removed**: it remains (a) the fallback when a
+   classname is missing from furnidata, and (b) the technical token for wired furni
+   (`Item.java:107-116` reads `fullName.startsWith("wf_")`). No schema migration. No DROP.
+3. There is **no `description` column** in `items_base`; description is JSON-only and has no
+   server consumer → the emulator gets **no** `getDescription()`.
+4. **One furnidata artifact** is shared truth: the file the emulator indexes must be the same
+   furnidata the client loads (deploy invariant, §7).
+5. Server emits names in the **base locale** of the furnidata file. Player-facing multi-language
+   stays a client localization-layer concern (unchanged).
+
+## 3. Architecture — two independent pieces
+
+The refactor is two pieces that share only the furnidata file and one new packet. They do not
+depend on each other.
+
+- **Piece 1 — Server-authoritative names.** The emulator's pronounced names come from furnidata.
+- **Piece 2 — Liveness via delta.** When the furnidata file changes, connected clients (and the
+  server index) update without reconnecting, via a minimal delta broadcast.
+
+## 4. Piece 1 — Emulator (server-authoritative names)
+
+### 4.1 `FurnidataReader` (new, package `com.eu.habbo.habbohotel.items`)
+
+A neutral, shared reader extracted so the editor is **not touched**. Responsibilities:
+
+- Resolve the furnidata source reusing the **same already-configured** path as the editor:
+  `furni.editor.renderer.config.path` → `furnidata.url` → `furni.editor.asset.base.path`
+  (see `FurniDataManager.resolveSource()` for the exact resolution we mirror). Default to those
+  values so admins configure **once**.
+- Support both layouts the editor already supports: **single file** (`FurnitureData.json`) and
+  **split-tier directory** (`core/custom/seasonal`, `manifest.json5`, JSON5 with comments;
+  later tiers override earlier). Reuse the JSON5 strip logic (extract to the shared reader).
+- Parse `roomitemtypes` (floor) and `wallitemtypes` (wall) → return a flat list of
+  `FurnidataEntry { int id, String classname, FurnitureType type, String name, String description }`.
+
+**Security requirements on the reader (furnidata is untrusted input):**
+
+- **Path-traversal guard.** When resolving split-tier manifest entries
+  (`tiers[]`, `files[]`) via `dir.resolve(name)`, normalize the result and **reject any path that
+  escapes the configured base dir** (absolute paths, `..`). The existing `FurniDataManager` lacks
+  this guard — the shared reader MUST add it (do not propagate the gap).
+- **Size cap.** Refuse to load a furnidata file/dir above a configurable max (default e.g. 64 MB)
+  to bound parse cost.
+- **Sanitization at the boundary.** Every `name`/`description` is sanitized on load:
+  truncate to **256 chars**, strip control characters and newlines, and **neutralize `%` tokens**
+  (so they cannot inject into `String.replace` placeholder chains, server- or wired-side).
+  Normal text/emoji/non-latin scripts pass through.
+- **Fail-safe.** Any IO/parse error is caught and logged; the provider keeps the **last-good
+  index** (or empty on first load) and never throws — boot must not crash on a bad furnidata.
+
+### 4.2 `FurnitureTextProvider` (new, package `items`)
+
+- Holds `volatile Map<String /*classname lowercase*/, FurniText {int id, String name, String description}>`.
+- `reindex()`: read via `FurnidataReader` → build a new immutable map → compute delta vs the
+  previous map (§5) → atomically swap the reference → return the delta.
+- Initialized in `GameEnvironment.load` near `ItemManager`. Resolution is **lazy**, so boot order
+  is not critical and `Item` objects do not depend on the provider at load time.
+- Toggle `items.furnidata.names.enabled` (default `true`). When `false`, `getDisplayName()`
+  returns the DB value (instant rollback, no recompile).
+
+### 4.3 `Item.getDisplayName()`
+
+```
+String getDisplayName():
+    if !enabled: return fullName
+    FurniText t = FurnitureTextProvider.get(this.name /* classname, lowercased */)
+    return (t != null && t.name not blank) ? t.name : this.fullName   // never null
+```
+
+No `getDescription()` on the server (no consumer).
+
+### 4.4 Swap list (exhaustive — verified)
+
+Replace `item.getFullName()` → `item.getDisplayName()` at exactly these 6 sites:
+
+| Site | Context |
+|---|---|
+| `CatalogBuyItemAsGiftEvent.java:251` | LTD daily-total alert (gift) |
+| `CatalogBuyItemAsGiftEvent.java:262` | LTD daily-item alert (gift) |
+| `CatalogManager.java:1057` | LTD daily-total alert (buy) |
+| `CatalogManager.java:1063` | LTD daily-item alert (buy) |
+| `WiredTextPlaceholderUtil.java:282` | wired `%furni.name%` (keep existing `getName()` ultimate fallback) |
+| `WatchAndEarnRewardComposer.java:21` | `appendString(...)` — sends name in a packet |
+
+**Do NOT change** (technical, use `item_name`/classname): `PresentItemOpenedComposer:24`,
+`GiftCommand:72`, `SendGift:82`, `SellItemEvent:37,45`, `CloseDiceEvent:34`, `isPet/isBot`, and the
+wired `wf_` fallback in `Item.load`. The catalog offer/page serialization sends **no** display
+name (`CatalogItem` serializes `catalog_name` + sprite only) — confirmed, nothing to change there.
+
+## 5. Piece 2 — Liveness via delta
+
+### 5.1 Server: file watcher + diff + broadcast
+
+- A `WatchService` watches the resolved furnidata location on a **single, serialized watcher
+  thread** (so reindex never races itself). For the **split-tier** layout, register the base dir
+  and each tier dir. **Debounce** (~750 ms) to coalesce burst writes, plus a **minimum interval
+  between broadcasts** (e.g. ≥5 s) to cap amplification.
+- On settle → `FurnitureTextProvider.reindex()` → diff old vs new **by classname**:
+  - **added** (new classname) and **changed** (name **or** description differs) → included.
+  - **removed** classnames → **ignored** (rare; resolved on client reconnect).
+- Broadcast decision (anti-DoS):
+  - delta empty → no broadcast.
+  - delta size ≤ **cap** (e.g. 500 entries) → broadcast `FurnitureDataReload` in **delta mode**.
+  - delta size > cap (mass replace) → broadcast in **reload-hint mode** (compact signal; clients
+    re-load furnidata at next opportunity) instead of a giant per-client payload.
+- The broadcast is triggered **only** by the file watcher — there is **no client-initiated reload
+  path**. This is a security property to preserve (clients cannot induce reindex/broadcast).
+
+### 5.2 Wire contract — new packet `FurnitureDataReload`
+
+- **Composer (Arcturus):** `FurnitureDataReloadComposer`, new dedicated header id (pick a free id;
+  document on both sides). Two modes:
+  ```
+  int   mode           // 0 = delta, 1 = reload-hint
+  // mode == 0 (delta):
+  int   count          // bounded by the server cap; the client MUST also bound it on read
+  count × {
+    string type        // "S" (floor) | "I" (wall)
+    int    id           // furnidata numeric id (for localization-key + FurnitureData lookup)
+    string classname
+    string name         // already sanitized server-side
+    string description
+  }
+  // mode == 1 (reload-hint): no further fields (optionally an int revision for cache-busting)
+  ```
+- **Parser/Event (renderer):** `FurnitureDataReloadEvent` + `FurnitureDataReloadParser` reading the
+  same shape. The parser **bounds `count`** (reject/clamp absurd values) and tolerates truncation
+  (`bytesAvailable` pattern) so a malformed/MITM payload cannot allocate unbounded memory.
+  Registered in `SessionDataManager.init()` via
+  `GetCommunication().registerMessageEvent(new FurnitureDataReloadEvent(...))` (same pattern as the
+  existing `FurniDataUpdatedEvent` registration, but a **distinct** handler).
+
+### 5.3 Renderer: separate patch path (no editor reuse)
+
+- New method, e.g. `SessionDataManager.applyFurnidataDelta(entries)` — **distinct** from the
+  editor's `applyLiveFurnitureNameUpdate(...)` (`SessionDataManager.ts:84`), which we leave intact.
+- **Delta mode (0):** for each entry, patch the corresponding `FurnitureData` (floor/wall, by `id`)
+  — update `_localizedName` and `_description` — and re-register the localization keys
+  `roomItem.name/desc.{id}` / `wallItem.name/desc.{id}` (mirrors `FurnitureDataLoader:105-110`).
+- **Reload-hint mode (1):** re-run the furnidata load (`FurnitureDataLoader`, re-fetching
+  `furnidata.url` with cache-bust) — the appropriate response to a mass change.
+- In both modes, after the batch dispatch the window event **once**:
+  `window.dispatchEvent(new CustomEvent('nitro-localization-updated'))`.
+
+### 5.4 Client: zero changes
+
+All three furni surfaces already subscribe to `nitro-localization-updated` and re-derive:
+
+- catalog — `useCatalog.ts:919`
+- inventory — `useInventoryFurni.ts:137` (→ `refreshGroupItemsLocalization`)
+- infostand — `useAvatarInfoWidget.ts:425` (→ `getFurniInfo`, which reads `furnitureData.name`)
+
+No Nitro-V3 edits are required for Piece 2.
+
+## 6. Admin-facing outcome
+
+Edit one place — the **furnidata JSON** — and display names update **live** across:
+server-pronounced strings (catalog LTD alerts, wired `%furni.name%`, Watch&Earn), and every
+connected client's catalog, inventory, and furni infostand. No DB edit, no restart, no double
+maintenance.
+
+## 7. Constraints, risks, invariants
+
+1. **Locale no-clobber.** If per-locale furni text override files are in use (they override
+   `roomItem.name.{id}` after furnidata load), a live delta that re-registers base names would
+   revert overridden ids to base. Mitigation options for the plan: re-apply active overrides after
+   the delta, or skip the localization-key patch for ids with an active override (still patch the
+   `FurnitureData` object). For single-furnidata setups (typical retro) there is no override and no
+   issue. **Document the limitation.**
+2. **Deploy invariant.** `furni.editor.asset.base.path`/`furnidata.url` (what the emulator watches)
+   and the furnidata the client loaded must be the **same artifact**, else the server delta
+   references entries the client doesn't have.
+3. **`public_name` fallback.** Wired `wf_` items absent from furnidata would show the raw `wf_…`
+   token as their display name (internal/invisible furni — acceptable).
+4. **Split-layout watcher.** The watcher must register all tier dirs; missing a tier dir means live
+   updates from that tier are not detected (resolved on reconnect).
+5. **Performance.** `getDisplayName()` is a single `HashMap` lookup on cold paths (catalog alerts,
+   wired text, Watch&Earn) — negligible.
+
+## 8. Security
+
+With this refactor the **furnidata becomes a security-relevant input**: its strings now flow into
+server output (catalog LTD alerts, wired `%furni.name%`, the Watch&Earn packet) and into a
+broadcast to every connected client. Regular players cannot influence names (names are admin-owned,
+keyed by classname); the threat is **untrusted furnidata content** (third-party furni packs,
+imports, a compromised editor/supply chain). Controls:
+
+1. **Boundary sanitization** (see §4.1): cap 256 chars, strip control/newline, **neutralize `%`**.
+   Neutralizing `%` at load makes every `String.replace("%itemname%", name)` /
+   `%furni.name%` site injection-safe; as defense-in-depth, substitute the (untrusted) furni name
+   **last** in any placeholder chain.
+2. **Path-traversal guard** in the shared reader (§4.1) — reject manifest paths escaping the base
+   dir. Closes a gap the current editor reader does not cover.
+3. **DoS / amplification controls** (§5.1): single serialized watcher thread, debounce + minimum
+   broadcast interval, delta-size cap with **reload-hint fallback** for mass changes, furnidata
+   file-size cap.
+4. **Fail-safe loading** (§4.1): bad/corrupt furnidata never crashes boot; last-good index is kept;
+   `getDisplayName()` falls back to `public_name`.
+5. **Robust client parser** (§5.2): bound `count`, tolerate truncation — a malformed/MITM
+   `FurnitureDataReload` cannot allocate unbounded memory client-side.
+6. **No client-triggered reload** (§5.1): only the file watcher broadcasts. Do not add any
+   client→server reload request. Preserve this property.
+7. **Minimal disclosure**: the delta carries **only** `name`/`description` (already public via
+   furnidata) — never other fields from the server-side file.
+8. **Concurrency**: `volatile` index reference + atomic swap + single reindex thread → no torn reads.
+
+## 9. Testing
+
+- **Emulator (JUnit):** `FurnidataReader` parses single-file and split-tier (JSON5, tier override);
+  `FurnitureTextProvider` lookup by lowercased classname, **fallback to `public_name`** when absent,
+  atomic reindex; `reindex()` diff produces correct added/changed delta and ignores removals;
+  `Item.getDisplayName()` honors the enable toggle.
+- **Renderer (Vitest):** `FurnitureDataReloadParser` reads the payload shape; `applyFurnidataDelta`
+  patches floor/wall `FurnitureData` by id, re-registers localization keys, dispatches
+  `nitro-localization-updated` once.
+- **Client (Vitest):** existing subscribers (`useCatalog`, `useInventoryFurni`, `useAvatarInfoWidget`)
+  refresh on `nitro-localization-updated` (regression guard; no new code).
+- **Manual acceptance:** edit a furni name in furnidata → live update in catalog + inventory +
+  infostand without refresh; a wired `%furni.name%` sign and a Watch&Earn reward show the new name.
+- **Security tests:** reader rejects a split-tier manifest with `../` traversal; a name containing
+  `%limit%`/`%user.name%` does not inject into catalog alerts or wired text (`%` neutralized);
+  oversized furnidata is refused; corrupt furnidata keeps last-good index and does not crash;
+  a mass change emits a reload-hint (not a giant delta); the client parser clamps an absurd `count`.
+
+## 10. Open questions
+
+- Free header id for `FurnitureDataReload` (assign during implementation; document both sides).
+- Whether any retro on this stack actually ships per-locale furni override files (governs whether
+  constraint §7.1 is live or moot).

packages/communication/src/index.ts

@@ -22,6 +22,7 @@ export * from './messages/incoming/crafting';
 export * from './messages/incoming/desktop';
 export * from './messages/incoming/friendlist';
 export * from './messages/incoming/furnieditor';
+export * from './messages/incoming/furniture';
 export * from './messages/incoming/game';
 export * from './messages/incoming/game/directory';
 export * from './messages/incoming/game/lobby';
@@ -181,6 +182,7 @@ export * from './messages/parser/crafting';
 export * from './messages/parser/desktop';
 export * from './messages/parser/friendlist';
 export * from './messages/parser/furnieditor';
+export * from './messages/parser/furniture';
 export * from './messages/parser/game';
 export * from './messages/parser/game/directory';
 export * from './messages/parser/game/lobby';

packages/communication/src/messages/incoming/IncomingHeader.ts

@@ -493,6 +493,7 @@ export class IncomingHeader
 	public static FURNI_EDITOR_DETAIL_RESULT = 10041;
 	public static FURNI_EDITOR_INTERACTIONS_RESULT = 10043;
 	public static FURNI_EDITOR_RESULT = 10044;
+	public static FURNITURE_DATA_RELOAD = 10047;
 
 	// Catalog Admin
     public static CATALOG_ADMIN_RESULT = 10059;

packages/communication/src/messages/incoming/furniture/FurnitureDataReloadEvent.ts

@@ -0,0 +1,16 @@
+import { IMessageEvent } from '@nitrots/api';
+import { MessageEvent } from '@nitrots/events';
+import { FurnitureDataReloadParser } from '../../parser/furniture/FurnitureDataReloadParser';
+
+export class FurnitureDataReloadEvent extends MessageEvent implements IMessageEvent
+{
+    constructor(callBack: Function)
+    {
+        super(callBack, FurnitureDataReloadParser);
+    }
+
+    public getParser(): FurnitureDataReloadParser
+    {
+        return this.parser as FurnitureDataReloadParser;
+    }
+}

packages/communication/src/messages/incoming/furniture/index.ts

@@ -0,0 +1 @@
+export * from './FurnitureDataReloadEvent';

packages/communication/src/messages/incoming/index.ts

@@ -14,6 +14,7 @@ export * from './crafting';
 export * from './desktop';
 export * from './friendlist';
 export * from './furnieditor';
+export * from './furniture';
 export * from './game';
 export * from './game/directory';
 export * from './game/lobby';

packages/communication/src/messages/parser/furniture/FurnitureDataReloadParser.ts

@@ -0,0 +1,56 @@
+import { IMessageDataWrapper, IMessageParser } from '@nitrots/api';
+
+export interface FurnidataDeltaEntry
+{
+    type: string;        // "S" floor | "I" wall
+    id: number;
+    classname: string;
+    name: string;
+    description: string;
+}
+
+export class FurnitureDataReloadParser implements IMessageParser
+{
+    private static readonly MAX_ENTRIES = 100000;
+
+    private _mode: number;
+    private _entries: FurnidataDeltaEntry[];
+
+    public flush(): boolean
+    {
+        this._mode = 0;
+        this._entries = [];
+        return true;
+    }
+
+    public parse(wrapper: IMessageDataWrapper): boolean
+    {
+        if(!wrapper) return false;
+
+        this._mode = wrapper.readInt();
+        this._entries = [];
+
+        if(this._mode === 0)
+        {
+            let count = wrapper.readInt();
+            if(count < 0) count = 0;
+            if(count > FurnitureDataReloadParser.MAX_ENTRIES) count = FurnitureDataReloadParser.MAX_ENTRIES;
+
+            for(let i = 0; i < count; i++)
+            {
+                this._entries.push({
+                    type: wrapper.readString(),
+                    id: wrapper.readInt(),
+                    classname: wrapper.readString(),
+                    name: wrapper.readString(),
+                    description: wrapper.readString()
+                });
+            }
+        }
+
+        return true;
+    }
+
+    public get mode(): number { return this._mode; }
+    public get entries(): FurnidataDeltaEntry[] { return this._entries; }
+}

packages/communication/src/messages/parser/furniture/index.ts

@@ -0,0 +1 @@
+export * from './FurnitureDataReloadParser';

packages/communication/src/messages/parser/index.ts

@@ -13,6 +13,7 @@ export * from './crafting';
 export * from './desktop';
 export * from './friendlist';
 export * from './furnieditor';
+export * from './furniture';
 export * from './game';
 export * from './game/directory';
 export * from './game/lobby';

packages/session/src/SessionDataManager.ts

@@ -1,5 +1,7 @@
 import { IFurnitureData, IGroupInformationManager, IMessageComposer, IMessageEvent, IProductData, ISessionDataManager, IUserDataSnapshot, NoobnessLevelEnum, SecurityLevel } from '@nitrots/api';
-import { AccountSafetyLockStatusChangeMessageEvent, AccountSafetyLockStatusChangeParser, AvailabilityStatusMessageEvent, ChangeUserNameResultMessageEvent, EmailStatusResultEvent, FigureUpdateEvent, GetCommunication, GetUserTagsComposer, InClientLinkEvent, MysteryBoxKeysEvent, NoobnessLevelMessageEvent, PetRespectComposer, PetScratchFailedMessageEvent, RoomReadyMessageEvent, RoomUnitChatComposer, UserInfoEvent, UserNameChangeMessageEvent, UserPermissionsEvent, UserRespectComposer, UserTagsMessageEvent } from '@nitrots/communication';
+import { AccountSafetyLockStatusChangeMessageEvent, AccountSafetyLockStatusChangeParser, AvailabilityStatusMessageEvent, ChangeUserNameResultMessageEvent, EmailStatusResultEvent, FigureUpdateEvent, FurnitureDataReloadEvent, GetCommunication, GetUserTagsComposer, InClientLinkEvent, MysteryBoxKeysEvent, NoobnessLevelMessageEvent, PetRespectComposer, PetScratchFailedMessageEvent, RoomReadyMessageEvent, RoomUnitChatComposer, UserInfoEvent, UserNameChangeMessageEvent, UserPermissionsEvent, UserRespectComposer, UserTagsMessageEvent } from '@nitrots/communication';
+import type { FurnidataDeltaEntry } from '@nitrots/communication';
+import { applyFurnidataDeltaTo } from './furniture/applyFurnidataDelta';
 import { GetConfiguration } from '@nitrots/configuration';
 import { GetLocalizationManager } from '@nitrots/localization';
 import { GetEventDispatcher, MysteryBoxKeysUpdateEvent, NitroEvent, NitroEventType, NitroSettingsEvent, SessionDataPreferencesEvent, UserNameUpdateEvent } from '@nitrots/events';
@@ -171,7 +173,13 @@ export class SessionDataManager implements ISessionDataManager
             GetCommunication().registerMessageEvent(new MysteryBoxKeysEvent(this.onMysteryBoxKeysEvent.bind(this))),
             GetCommunication().registerMessageEvent(new NoobnessLevelMessageEvent(this.onNoobnessLevelMessageEvent.bind(this))),
             GetCommunication().registerMessageEvent(new AccountSafetyLockStatusChangeMessageEvent(this.onAccountSafetyLockStatusChangeMessageEvent.bind(this))),
-            GetCommunication().registerMessageEvent(new EmailStatusResultEvent(this.onEmailStatus.bind(this)))
+            GetCommunication().registerMessageEvent(new EmailStatusResultEvent(this.onEmailStatus.bind(this))),
+            GetCommunication().registerMessageEvent(new FurnitureDataReloadEvent((event: FurnitureDataReloadEvent) =>
+            {
+                const parser = event.getParser();
+                if(parser.mode === 1) { void this.applyFurnidataReloadHint(); }
+                else { this.applyFurnidataDelta(parser.entries); }
+            }))
         );
 
         // Store event dispatcher callback for cleanup
@@ -564,6 +572,17 @@ export class SessionDataManager implements ISessionDataManager
         }
     }
 
+    public applyFurnidataDelta(entries: FurnidataDeltaEntry[]): void
+    {
+        applyFurnidataDeltaTo(entries, this._floorItems as any, this._wallItems as any, GetLocalizationManager(), (typeof window !== 'undefined') ? window : { dispatchEvent: () => {} } as any);
+    }
+
+    public async applyFurnidataReloadHint(): Promise<void>
+    {
+        await this._furnitureData.init();
+        if(typeof window !== 'undefined') window.dispatchEvent(new CustomEvent('nitro-localization-updated'));
+    }
+
     public getBadgeUrl(name: string): string
     {
         return this._badgeImageManager.getBadgeUrl(name);

packages/session/src/__tests__/applyFurnidataDelta.test.ts

@@ -0,0 +1,36 @@
+import { describe, expect, it, vi, beforeEach } from 'vitest';
+import { applyFurnidataDeltaTo } from '../furniture/applyFurnidataDelta';
+
+describe('applyFurnidataDeltaTo', () => {
+    const setValue = vi.fn();
+    beforeEach(() => setValue.mockClear());
+
+    it('patches floor FurnitureData name/desc + localization keys, dispatches window event', () => {
+        const floor: any = { _localizedName: 'Old', _description: 'Old desc' };
+        const floorItems = new Map<number, any>([[ 5, floor ]]);
+        const dispatched: string[] = [];
+        const win: any = { dispatchEvent: (e: any) => dispatched.push(e.type) };
+
+        applyFurnidataDeltaTo(
+            [ { type: 'S', id: 5, classname: 'chair', name: 'New', description: 'New desc' } ],
+            floorItems, new Map(), { setValue }, win
+        );
+
+        expect(floor._localizedName).toBe('New');
+        expect(floor._description).toBe('New desc');
+        expect(setValue).toHaveBeenCalledWith('roomItem.name.5', 'New');
+        expect(setValue).toHaveBeenCalledWith('roomItem.desc.5', 'New desc');
+        expect(dispatched).toContain('nitro-localization-updated');
+    });
+
+    it('patches wall items by id', () => {
+        const wall: any = { _localizedName: 'W', _description: '' };
+        const wallItems = new Map<number, any>([[ 9, wall ]]);
+        applyFurnidataDeltaTo(
+            [ { type: 'I', id: 9, classname: 'poster', name: 'WallNew', description: 'd' } ],
+            new Map(), wallItems, { setValue }, { dispatchEvent: () => {} }
+        );
+        expect(wall._localizedName).toBe('WallNew');
+        expect(setValue).toHaveBeenCalledWith('wallItem.name.9', 'WallNew');
+    });
+});

packages/session/src/furniture/applyFurnidataDelta.ts

@@ -0,0 +1,43 @@
+import type { FurnidataDeltaEntry } from '@nitrots/communication';
+
+/**
+ * Pure, testable furnidata-delta patcher. Mutates the FurnitureData objects in
+ * the given maps (by id) and the localization keys, then dispatches the
+ * `nitro-localization-updated` window event so subscribed React surfaces refresh.
+ */
+export function applyFurnidataDeltaTo(
+    entries: FurnidataDeltaEntry[],
+    floorItems: Map<number, any>,
+    wallItems: Map<number, any>,
+    localization: { setValue: (key: string, value: string) => void },
+    win: { dispatchEvent: (event: any) => void }
+): void
+{
+    if(!entries || !entries.length) return;
+
+    for(const e of entries)
+    {
+        if(e.type === 'I')
+        {
+            const wall = wallItems.get(e.id);
+            if(wall) { wall._localizedName = e.name; wall._description = e.description; }
+            localization.setValue('wallItem.name.' + e.id, e.name);
+            localization.setValue('wallItem.desc.' + e.id, e.description);
+        }
+        else
+        {
+            const floor = floorItems.get(e.id);
+            if(floor) { floor._localizedName = e.name; floor._description = e.description; }
+            localization.setValue('roomItem.name.' + e.id, e.name);
+            localization.setValue('roomItem.desc.' + e.id, e.description);
+        }
+    }
+
+    if(win && typeof win.dispatchEvent === 'function')
+    {
+        const evt = (typeof CustomEvent !== 'undefined')
+            ? new CustomEvent('nitro-localization-updated')
+            : { type: 'nitro-localization-updated' } as any;
+        win.dispatchEvent(evt);
+    }
+}