feat(render): M2 — React 渲染内核 + 布局画廊(playground)

- core 新增 render 子路径(vibe-registry/render):PageView + WidgetView + LayoutGallery
- layout 注册项支持 render 实现;缺省兜底 DefaultLayout
- widget 注册项 component 挂真实 React 组件
- PageBlockDecl 增加 slot 字段(块落在布局哪个槽位)
- playground:admin 布局真实骨架 + 组件 + 订单页,dev 预览 + 生产构建通过
- 全量回归:core/qa-orchestrator/playground typecheck 全绿

examples/playground/tsconfig.json

@@ -0,0 +1,17 @@
+{
+  "compilerOptions": {
+    "target": "ES2022",
+    "module": "ESNext",
+    "moduleResolution": "Bundler",
+    "lib": ["ES2022", "DOM", "DOM.Iterable"],
+    "jsx": "react-jsx",
+    "allowImportingTsExtensions": true,
+    "strict": true,
+    "noEmit": true,
+    "esModuleInterop": true,
+    "skipLibCheck": true,
+    "forceConsistentCasingInFileNames": true,
+    "types": ["vite/client"]
+  },
+  "include": ["src", "vite.config.ts"]
+}