task(CAD-14): phase 2 - stale closure fix (onElementCreatedRef), debug expose docCount/announcedCount, overlay handles for pixi mode

frontend/src/components/CanvasArea.tsx

@@ -41,8 +41,11 @@ const CanvasArea: React.FC<CanvasAreaProps> = ({
   const pixiRendererRef = useRef<PixiRenderer | null>(null);
   /** CAD-13-fix: Bereits in Pixi gespiegelte Bestands-Elemente (id -> Referenz). */
   const pixiMirrorRef = useRef<Map<string, CADElement>>(new Map());
-  /** Bereits an onElementCreated gemeldete V2-Element-IDs (verhindert Doppelmeldung bei jedem onChanged-Frame). */
+  /** CAD-14: Bereits an onElementCreated gemeldete V2-Element-IDs (verhindert Doppelmeldung bei jedem onChanged-Frame). */
   const announcedV2Ids = useRef<Set<string>>(new Set());
+  /** CAD-14: Frische Prop-Referenz gegen Stale-Closure (Dispatcher/onChanged sind einmalig registriert). */
+  const onElementCreatedRef = useRef(onElementCreated);
+  onElementCreatedRef.current = onElementCreated;
   const spatialIndexRef = useRef<SpatialIndex | null>(null);
   const layerManagerRef = useRef<LayerManager | null>(null);
   const selectionEngineRef = useRef<SelectionEngine | null>(null);
@@ -92,6 +95,8 @@ const CanvasArea: React.FC<CanvasAreaProps> = ({
             (window as unknown as { __v2Debug: unknown }).__v2Debug = {
               renderer: pixi,
               info: () => pixiRendererRef.current?.getDebugInfo() ?? null,
+              docCount: () => v2Doc.getAllElements().length,
+              announcedCount: () => announcedV2Ids.current.size,
             };
           }).catch((err) => {
             logger.warn('Pixi init failed — V2-Overlay deaktiviert:', err);
@@ -146,7 +151,9 @@ const CanvasArea: React.FC<CanvasAreaProps> = ({
         for (const el of v2Doc.getAllElements()) {
           if (!announcedV2Ids.current.has(el.id)) {
             announcedV2Ids.current.add(el.id);
-            onElementCreated(el);
+            // CAD-14: ueber Ref — die eingefrorene Prop haette eine alte
+            // drawingId-Closure (still kein DB-Save nach Spaet-Mount).
+            onElementCreatedRef.current(el);
           }
         }
         syncPixi();  // Task C2: V2-Elemente in den PixiJS-Overlay-Renderer spiegeln
@@ -322,6 +329,8 @@ const CanvasArea: React.FC<CanvasAreaProps> = ({
         } as never;
         for (const el of elements) {
           currentIds.add(el.id);
+          // CAD-14: V2-stämmige Elemente zeichnet syncPixi (v2Doc.onChanged) —
+          // hier NUR noch Aktualisierung des Spiegels, kein doppeltes drawElement.
           if (mirror.get(el.id) !== el) {
             mirror.set(el.id, el);
             const layer = layers.find((l) => l.id === el.layerId) ?? layerFallback;