feat: 添加 topic_id 字段到消息结构，优化消息处理逻辑

src/protocol/mod.rs

@@ -202,6 +202,8 @@ pub enum WsOutbound {
         task_id: String,
         description: String,
         subagent_type: String,
+        #[serde(default, skip_serializing_if = "Option::is_none")]
+        topic_id: Option<String>,
     },
     #[serde(rename = "session_established")]
     SessionEstablished { session_id: String },

src/protocol/ws_adapter.rs

@@ -172,6 +172,7 @@ pub(crate) fn ws_outbound_from_outbound_message(message: &OutboundMessage) -> Ve
             task_id: message.metadata.get("task_id").cloned().unwrap_or_default(),
             description: message.metadata.get("task_description").cloned().unwrap_or_default(),
             subagent_type: message.metadata.get("task_subagent_type").cloned().unwrap_or_default(),
+            topic_id: message.metadata.get("topic_id").cloned(),
         }],
     }
 }

src/tools/task/runtime.rs

@@ -250,6 +250,7 @@ impl DefaultSubAgentRuntime {
                 let mut metadata = HashMap::new();
                 metadata.insert("subagent_task_id".to_string(), session.id.clone());
                 metadata.insert("is_subagent_event".to_string(), "true".to_string());
+                metadata.insert("topic_id".to_string(), session.parent_topic_id.clone().unwrap_or_default());
 
                 let emitter = Arc::new(PersistingEmittedMessageHandler::new(
                     SubAgentEmitter {
@@ -424,6 +425,7 @@ impl SubAgentRuntime for DefaultSubAgentRuntime {
             metadata.insert("task_id".to_string(), session.id.clone());
             metadata.insert("task_description".to_string(), session.description.clone());
             metadata.insert("task_subagent_type".to_string(), session.subagent_type.clone());
+            metadata.insert("topic_id".to_string(), session.parent_topic_id.clone().unwrap_or_default());
 
             let event = OutboundMessage {
                 channel: session.parent_channel_name.clone(),

web/src/hooks/useChat.ts

@@ -181,6 +181,15 @@ export function useChat(): UseChatReturn {
     return undefined
   }
 
+  // Extract topic_id from a message if present
+  const getTopicId = (message: WsOutbound): string | undefined => {
+    if (message.type === 'tool_call' || message.type === 'tool_result'
+        || message.type === 'tool_pending' || message.type === 'assistant_response') {
+      return (message as ToolCall | ToolResult | ToolPending | AssistantResponse).topic_id
+    }
+    return undefined
+  }
+
   // Convert a server message to ChatMessage (extracted from handleServerMessage logic)
   const serverMessageToChatMessage = (message: WsOutbound): ChatMessage | null => {
     switch (message.type) {
@@ -311,12 +320,20 @@ export function useChat(): UseChatReturn {
         appendToSubAgentViewMessage(message)
         return
       }
+      // 丢弃其他子智能体的消息，避免 fall through 到主消息处理
+      if (msgSubagentTaskId) {
+        return
+      }
     }
 
     // In main view, skip sub-agent messages (they belong to sub-agent view).
     // But use the task_id to associate with the running task tool card.
     const msgSubagentTaskId = getSubagentTaskId(message)
     if (msgSubagentTaskId) {
+      // 只 backfill 当前话题的 task tool_call，避免跨话题串扰
+      const msgTopicId = getTopicId(message)
+      if (msgTopicId && msgTopicId !== selectedTopicRef.current) return
+
       setMessages((prev) => {
         for (let i = prev.length - 1; i >= 0; i--) {
           if (prev[i].type === 'tool_call' && prev[i].toolName === 'task' && !prev[i].subagentTaskId) {
@@ -340,6 +357,9 @@ export function useChat(): UseChatReturn {
 
       case 'task_started': {
         const msg = message as TaskStarted
+        // 只 backfill 当前话题的 task tool_call，避免跨话题串扰
+        if (msg.topic_id && msg.topic_id !== selectedTopicRef.current) break
+
         // 立即更新对应的 task tool_call，让用户可以点击查看实时进度
         setMessages((prev) => {
           for (let i = prev.length - 1; i >= 0; i--) {
@@ -602,6 +622,7 @@ export function useChat(): UseChatReturn {
   const selectTopic = useCallback((topicId: string) => {
     setSelectedTopic(topicId)
     setMessages([])
+    setSubAgentView(null)
   }, [])
 
   const createTopic = useCallback((title?: string): Command => {
@@ -647,6 +668,7 @@ export function useChat(): UseChatReturn {
     setTopics([])
     setSelectedTopic(null)
     setMessages([])
+    setSubAgentView(null)
     setIsLoading(true)
   }, [selectedChannel])
 
@@ -656,6 +678,7 @@ export function useChat(): UseChatReturn {
     setTopics([])
     setSelectedTopic(null)
     setMessages([])
+    setSubAgentView(null)
     setIsLoading(true)
   }, [selectedSessionId])
 

web/src/types/protocol.ts

@@ -100,6 +100,7 @@ export interface TaskStarted {
   task_id: string
   description: string
   subagent_type: string
+  topic_id?: string
 }
 
 export interface SessionEstablished {