Add end-to-end tests for workspace switching and backend tests for ask_question tool

- Implemented E2E tests for workspace switching functionality, covering scenarios such as switching workspaces, data isolation, language preference maintenance, and UI updates.
- Added tests to ensure workspace data is cleared on logout and handles unsaved changes during workspace switches.
- Created comprehensive backend tests for the ask_question tool, validating question creation, execution, answer handling, cancellation, and timeout scenarios.
- Included edge case tests to ensure robustness against duplicate questions and invalid answers.

ccw/frontend/src/hooks/useWebSocket.ts

@@ -219,6 +219,7 @@ export function useWebSocket(options: UseWebSocketOptions = {}): UseWebSocketRet
       completeExecution,
       updateNode,
       addOutput,
+      addA2UINotification,
       onMessage,
     ]
   );
@@ -314,7 +315,20 @@ export function useWebSocket(options: UseWebSocketOptions = {}): UseWebSocketRet
       connect();
     }
 
+    // Listen for A2UI action events and send via WebSocket
+    const handleA2UIAction = (event: CustomEvent) => {
+      if (wsRef.current?.readyState === WebSocket.OPEN) {
+        wsRef.current.send(JSON.stringify(event.detail));
+      } else {
+        console.warn('[WebSocket] Cannot send A2UI action: not connected');
+      }
+    };
+
+    // Type the event listener properly
+    window.addEventListener('a2ui-action', handleA2UIAction as EventListener);
+
     return () => {
+      window.removeEventListener('a2ui-action', handleA2UIAction as EventListener);
       if (reconnectTimeoutRef.current) {
         clearTimeout(reconnectTimeoutRef.current);
       }