wired-tools: hoist variable-highlight toggle + overlays to the store

Move the highlight feature pair into useWiredCreatorToolsUiStore:
isVariableHighlightActive (toggle UI flag) and variableHighlightOverlays
(computed screen-space overlay positions). The two screen-coords effects
in WiredCreatorToolsView stay where they are (they need React's
lifecycle to install / tear down WiredSelectionVisualizer highlights on
the active room objects) but now write to setVariableHighlightOverlays.

WiredVariablesTabView drops the isVariableHighlightActive +
onToggleVariableHighlight props and consumes the store directly — same
shape as the previous tab-prop reductions on this branch. The toggle
button keeps the same UX (Highlight ↔ Undo) but no longer crosses the
prop boundary.

Direct benefit: closing and reopening the panel while a variable
highlight is active no longer flickers the overlays off and back on —
the active flag + the last-computed overlay set both persist in
zustand and the effect re-runs from the same starting point.

Tests: three new cases on the store (toggle via direct + updater,
overlay replace + clear, close/reopen persistence). 190/190 passing.

variableHighlightObjectsRef stays a useRef inside the component: it
tracks the live PIXI objects WiredSelectionVisualizer drew onto, used
only for the cleanup pass — refs don't trigger renders and don't need
to live in the store.

src/components/wired-tools/wiredCreatorToolsUiStore.test.ts

@@ -22,7 +22,9 @@ const INITIAL = {
     selectedFurniLiveState: null,
     selectedUser: null,
     selectedUserLiveState: null,
-    selectedUserActionVersion: 0
+    selectedUserActionVersion: 0,
+    isVariableHighlightActive: false,
+    variableHighlightOverlays: []
 };
 
 describe('useWiredCreatorToolsUiStore', () =>
@@ -56,6 +58,8 @@ describe('useWiredCreatorToolsUiStore', () =>
         expect(state.selectedUser).toBeNull();
         expect(state.selectedUserLiveState).toBeNull();
         expect(state.selectedUserActionVersion).toBe(0);
+        expect(state.isVariableHighlightActive).toBe(false);
+        expect(state.variableHighlightOverlays).toEqual([]);
     });
 
     describe('setIsVisible', () =>
@@ -314,4 +318,42 @@ describe('useWiredCreatorToolsUiStore', () =>
             expect(useWiredCreatorToolsUiStore.getState().selectedFurni).toEqual(furniSelection);
         });
     });
+
+    describe('variable highlight', () =>
+    {
+        const overlay = { itemId: 1, key: 'foo', x: 100, y: 200, screenX: 100, screenY: 200, value: '42', objectId: 7, category: 10 } as never;
+
+        it('setIsVariableHighlightActive accepts a direct boolean and a toggle updater', () =>
+        {
+            useWiredCreatorToolsUiStore.getState().setIsVariableHighlightActive(true);
+            expect(useWiredCreatorToolsUiStore.getState().isVariableHighlightActive).toBe(true);
+
+            useWiredCreatorToolsUiStore.getState().setIsVariableHighlightActive(prev => !prev);
+            expect(useWiredCreatorToolsUiStore.getState().isVariableHighlightActive).toBe(false);
+
+            useWiredCreatorToolsUiStore.getState().setIsVariableHighlightActive(prev => !prev);
+            expect(useWiredCreatorToolsUiStore.getState().isVariableHighlightActive).toBe(true);
+        });
+
+        it('setVariableHighlightOverlays replaces the overlay array', () =>
+        {
+            useWiredCreatorToolsUiStore.getState().setVariableHighlightOverlays([ overlay ]);
+            expect(useWiredCreatorToolsUiStore.getState().variableHighlightOverlays).toEqual([ overlay ]);
+
+            useWiredCreatorToolsUiStore.getState().setVariableHighlightOverlays([]);
+            expect(useWiredCreatorToolsUiStore.getState().variableHighlightOverlays).toEqual([]);
+        });
+
+        it('the highlight survives a panel close/reopen lifecycle', () =>
+        {
+            useWiredCreatorToolsUiStore.getState().setIsVariableHighlightActive(true);
+            useWiredCreatorToolsUiStore.getState().setVariableHighlightOverlays([ overlay ]);
+
+            useWiredCreatorToolsUiStore.getState().setIsVisible(false);
+            useWiredCreatorToolsUiStore.getState().setIsVisible(true);
+
+            expect(useWiredCreatorToolsUiStore.getState().isVariableHighlightActive).toBe(true);
+            expect(useWiredCreatorToolsUiStore.getState().variableHighlightOverlays).toEqual([ overlay ]);
+        });
+    });
 });