feat(a2ui): Implement A2UI backend with question handling and WebSocket support

- Added A2UITypes for defining question structures and answers.
- Created A2UIWebSocketHandler for managing WebSocket connections and message handling.
- Developed ask-question tool for interactive user questions via A2UI.
- Introduced platformUtils for platform detection and shell command handling.
- Centralized TypeScript types in index.ts for better organization.
- Implemented compatibility checks for hook templates based on platform requirements.

ccw/frontend/src/locales/zh/workspace.json

@@ -0,0 +1,29 @@
+{
+  "selector": {
+    "noWorkspace": "未选择工作空间",
+    "recentPaths": "最近的项目",
+    "noRecentPaths": "没有最近的项目",
+    "current": "当前",
+    "browse": "选择文件夹...",
+    "removePath": "从最近记录中移除",
+    "ariaLabel": "工作空间选择器"
+  },
+  "dialog": {
+    "title": "选择项目文件夹",
+    "placeholder": "输入项目路径...",
+    "help": "您的项目目录路径"
+  },
+  "actions": {
+    "switch": "切换工作空间",
+    "switchFailed": "切换工作空间失败",
+    "switchSuccess": "成功切换到 {path}"
+  },
+  "validation": {
+    "pathRequired": "项目路径不能为空",
+    "invalidPath": "无效的项目路径：{path}"
+  },
+  "notifications": {
+    "switching": "正在切换工作空间...",
+    "refreshing": "正在刷新最近路径..."
+  }
+}