feat: M5 外观特效选择+持久化（appearance:load/save IPC+config.json，鼠效 6 选格接 EffectEngine，重开恢复并接线）

apps/desktop/src/renderer/features/effects/EffectLayer.tsx

@@ -5,16 +5,25 @@ import { useAppearance } from '../appearance/appearance-store';
 export function EffectLayer() {
   const ref = useRef<HTMLCanvasElement>(null);
   const engineRef = useRef<EffectEngine | null>(null);
-  const appearance = useAppearance();
-  // M6 骨架：默认关闭，外观面板后续接入选择
+  const effect = useAppearance(s => s.effect);
+  const accent = useAppearance(s => s.draft.accent);
+
+  // 建引擎一次
   useEffect(() => {
     if (!ref.current) return;
     const eng = new EffectEngine();
     eng.attach(ref.current);
-    eng.setColor(appearance.draft.accent);
-    eng.setType('off'); // 默认关闭，待外观面板接入开启
     engineRef.current = eng;
     return () => eng.detach();
   }, []);
-  return <canvas ref={ref} style={{ position: 'fixed', inset: 0, pointerEvents: 'none', zIndex: 9999 }} />;
+
+  // effect/accent 变化时同步引擎（FR-A11 接线）
+  useEffect(() => {
+    const eng = engineRef.current;
+    if (!eng) return;
+    eng.setColor(accent);
+    eng.setType(effect);
+  }, [effect, accent]);
+
+  return <canvas ref={ref} data-effect={effect} style={{ position: 'fixed', inset: 0, pointerEvents: 'none', zIndex: 9999 }} />;
 }