fix: session reconnect catch-up, always-on input, frozen session recovery (#524)

- WebSocketContext: emit 'websocket-reconnected' on onopen when it's a reconnect
  (hasConnectedRef tracks first-connect vs. subsequent reconnects).
- useChatRealtimeHandlers: handle 'websocket-reconnected' via onWebSocketReconnect
  callback; added to globalMessageTypes to bypass sessionId mismatch checks.
- ChatInterface: on reconnect, re-fetch JSONL session history so messages missed
  during iOS background are shown immediately. Also resets isLoading and
  canAbortSession so a dead/restarted session no longer freezes the UI forever.
- ChatComposer: remove disabled={isLoading} from textarea — users can always
  type regardless of processing state; submit button still prevents double-send.

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

src/components/chat/hooks/useChatRealtimeHandlers.ts

@@ -48,6 +48,7 @@ interface UseChatRealtimeHandlersArgs {
   onSessionNotProcessing?: (sessionId?: string | null) => void;
   onReplaceTemporarySession?: (sessionId?: string | null) => void;
   onNavigateToSession?: (sessionId: string) => void;
+  onWebSocketReconnect?: () => void;
 }
 
 const appendStreamingChunk = (
@@ -113,6 +114,7 @@ export function useChatRealtimeHandlers({
   onSessionNotProcessing,
   onReplaceTemporarySession,
   onNavigateToSession,
+  onWebSocketReconnect,
 }: UseChatRealtimeHandlersArgs) {
   const lastProcessedMessageRef = useRef<LatestChatMessage | null>(null);
 
@@ -136,7 +138,7 @@ export function useChatRealtimeHandlers({
         : null;
     const messageType = String(latestMessage.type);
 
-    const globalMessageTypes = ['projects_updated', 'taskmaster-project-updated', 'session-created'];
+    const globalMessageTypes = ['projects_updated', 'taskmaster-project-updated', 'session-created', 'websocket-reconnected'];
     const isGlobalMessage = globalMessageTypes.includes(messageType);
     const lifecycleMessageTypes = new Set([
       'claude-complete',
@@ -300,6 +302,11 @@ export function useChatRealtimeHandlers({
         }
         break;
 
+      case 'websocket-reconnected':
+        // WebSocket dropped and reconnected — re-fetch session history to catch up on missed messages
+        onWebSocketReconnect?.();
+        break;
+
       case 'token-budget':
         if (latestMessage.data) {
           setTokenBudget(latestMessage.data);