React 19 modernization: forwardRef removal, Compiler, ErrorBoundary, Suspense, native <script>

Adopt React 19 idioms across the codebase. The runtime was already on
react@19.2.5 but no React 19 APIs were in use.

- forwardRef -> ref-as-prop in 7 layout/component files
  (NitroInput/Button/ItemCountBadge/Card×5/InfiniteGridItem,
  ToolbarItemView, AvatarEditorIcon)
- <Ctx.Provider> -> <Ctx> in 6 contexts (CatalogAdmin, FloorplanEditor,
  UiSettings, GridContext, NitroCardContext, NitroCardAccordionContext)
- Native <script> hoisting for Turnstile, ExternalPluginLoader, GoogleAdsView
  (React 19 dedupes by src; removes manual document.head.appendChild +
  module-level promise caches)
- React Compiler enabled at build time via babel-plugin-react-compiler
  in vite.config.mjs (target: '19'), plus eslint-plugin-react-compiler
  in lint mode
- Global <ErrorBoundary> + <Suspense> in src/index.tsx using
  react-error-boundary, with LoadingView as fallback
- BackgroundsView migrated to use(promise) as a demonstrator pattern
  for Suspense-driven config loading
- ESLint react setting bumped 18.3.1 -> 19.2; legacy
  @typescript-eslint/ban-types replaced with no-restricted-types
  (the old rule was removed in @typescript-eslint v8)
- Refresh public/configuration/{asset-loader,bootstrap}.js to match
  current write-asset-loader.mjs output

Phase 3 (login forms -> useActionState/useFormStatus) deferred:
LoginView is 1623 lines with lockout + Turnstile + heartbeat
interleaving; safer as its own PR.

https://claude.ai/code/session_01GrR87LAqnAEyKG2ZbmQt5Q

src/components/plugins/ExternalPluginLoader.tsx

@@ -2,29 +2,25 @@ import { FC, useEffect, useState } from 'react';
 import { GetConfigurationValue } from '../../api';
 import { subscribePlugins } from './NitroPluginApi';
 
-// Force the global API to be initialized
 import './NitroPluginApi';
 
 export const ExternalPluginLoader: FC<{}> = () =>
 {
     const [, forceUpdate] = useState(0);
+    const [ pluginUrls, setPluginUrls ] = useState<string[]>([]);
 
     useEffect(() =>
     {
         return subscribePlugins(() => forceUpdate(n => n + 1));
     }, []);
 
-    // MainView only renders after isReady=true in App.tsx,
-    // so the configuration is guaranteed to be loaded at this point.
     useEffect(() =>
     {
-        const scripts: HTMLScriptElement[] = [];
-
-        let pluginUrls: string[] = [];
+        let urls: string[] = [];
 
         try
         {
-            pluginUrls = GetConfigurationValue<string[]>('external.plugins', []);
+            urls = GetConfigurationValue<string[]>('external.plugins', []) || [];
         }
         catch (e)
         {
@@ -32,30 +28,28 @@ export const ExternalPluginLoader: FC<{}> = () =>
             return;
         }
 
-        if (!pluginUrls || pluginUrls.length === 0)
+        if (!urls.length)
         {
             console.log('[NitroPlugins] No external plugins configured');
             return;
         }
 
-        console.log('[NitroPlugins] Loading external plugins:', pluginUrls);
-
-        for (const url of pluginUrls)
-        {
-            const script = document.createElement('script');
-            script.src = url;
-            script.async = true;
-            script.onload = () => console.log(`[NitroPlugins] Loaded: ${url}`);
-            script.onerror = () => console.warn(`[NitroPlugins] Failed to load: ${url}`);
-            document.head.appendChild(script);
-            scripts.push(script);
-        }
-
-        return () =>
-        {
-            scripts.forEach(s => s.remove());
-        };
+        console.log('[NitroPlugins] Loading external plugins:', urls);
+        setPluginUrls(urls);
     }, []);
 
-    return null;
+    if (!pluginUrls.length) return null;
+
+    return (
+        <>
+            { pluginUrls.map(url => (
+                <script
+                    key={ url }
+                    async
+                    src={ url }
+                    onLoad={ () => console.log(`[NitroPlugins] Loaded: ${ url }`) }
+                    onError={ () => console.warn(`[NitroPlugins] Failed to load: ${ url }`) } />
+            )) }
+        </>
+    );
 };