fix: resolve task resumption stalling and improve error handling

- Add timeout handling for resume state to prevent indefinite waiting
- Fix resumeTask function to properly handle new content without duplication
- Improve server-side resume logic with fallback to new task on timeout
- Add better validation and logging for resume operations

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: 2 people

demo/package-lock.json

@@ -69,18 +69,28 @@ wss.on('connection', (ws, req) => {
 
   // If resuming, wait for the state before starting the task
   if (isResume) {
-    pendingState = new Promise((resolve) => {
+    pendingState = new Promise((resolve, reject) => {
+      let timeout;
       const stateHandler = (message) => {
         try {
           const data = JSON.parse(message.toString());
           if (data.type === 'resume_state') {
+            clearTimeout(timeout);
             resolve(data.finalState);
             ws.removeListener('message', stateHandler);
           }
         } catch (error) {
           console.error('State parse error:', error);
         }
       };
+      
+      // Set timeout for resume state
+      timeout = setTimeout(() => {
+        console.warn(`⏰ Resume state timeout for session ${sessionId}, falling back to new task`);
+        ws.removeListener('message', stateHandler);
+        resolve(null); // Resolve with null to fallback to regular task
+      }, 5000);
+      
       ws.on('message', stateHandler);
     });
   }
@@ -94,11 +104,17 @@ wss.on('connection', (ws, req) => {
 
     if (isResume && pendingState) {
       const finalState = await pendingState;
-      console.log(`📋 Resuming task with ${finalState.messages.length} messages`);
-      
-      taskController = startDemoTask(prompt, (data) => {
-        ws.send(JSON.stringify(data));
-      }, { ...options, finalState, isResume: true });
+      if (finalState && finalState.messages && finalState.messages.length > 0) {
+        console.log(`📋 Resuming task with ${finalState.messages.length} messages`);
+        taskController = startDemoTask(prompt, (data) => {
+          ws.send(JSON.stringify(data));
+        }, { ...options, finalState, isResume: true });
+      } else {
+        console.log(`⚠️  Resume failed or no state, starting new task`);
+        taskController = startDemoTask(prompt, (data) => {
+          ws.send(JSON.stringify(data));
+        }, options);
+      }
     } else {
       taskController = startDemoTask(prompt, (data) => {
         ws.send(JSON.stringify(data));

demo/server.js

@@ -111,10 +111,16 @@ export function resumeTask(
             content: newContent,
             id: uuidv4()
         });
+        
+        // Update the finalState with the new messages
+        finalState.messages = messages;
+        
+        // Resume with the full state, using a placeholder content since we already added the message
+        return runTask(agent, 'Resume task', finalState);
     }
 
-    // Resume with the full state
-    return runTask(agent, newContent || 'Continue with the task', finalState);
+    // Resume with the full state without adding new content
+    return runTask(agent, 'Continue with the task', finalState);
 }
 
 /**