fix: synchronize local message state after conversation compaction (#5315)

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

ui/desktop/src/hooks/useChatStream.ts

@@ -176,6 +176,7 @@ async function streamFromResponse(
             }
             case 'UpdateConversation': {
               log.messages('conversation-update', event.conversation.length);
+              currentMessages = event.conversation;
               // This calls the wrapped setMessagesAndLog with 'streaming' context
               updateMessages(event.conversation);
               break;

ui/desktop/src/hooks/useMessageStream.ts

@@ -330,6 +330,7 @@ export function useMessageStream({
                   }
 
                   case 'UpdateConversation': {
+                    currentMessages = parsedEvent.conversation;
                     setMessages(parsedEvent.conversation);
                     break;
                   }