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/pages/FixSessionPage.tsx

@@ -192,7 +192,7 @@ export function FixSessionPage() {
               <Wrench className="h-5 w-5" />
               {formatMessage({ id: 'fixSession.progress.title' })}
             </h3>
-            <Badge variant="secondary">{session.phase || 'Execution'}</Badge>
+            <Badge variant="secondary">{session.phase || formatMessage({ id: 'fixSession.phase.execution' })}</Badge>
           </div>
 
           {/* Progress Bar */}