guard stale init effects

web/app/chat/page.js

@@ -152,6 +152,8 @@ function ChatPage() {
   useEffect(() => {
     if (!token || authLoading) return;
 
+    let stale = false;
+
     async function init() {
       setLoadingConv(true);
       setError(null);
@@ -163,6 +165,7 @@ function ChatPage() {
           const res = await fetch(`${API_BASE}/api/v1/chat/conversations`, {
             headers: { Authorization: `Bearer ${token}` },
           });
+          if (stale) return;
           if (res.ok) {
             const list = await res.json();
             const open = Array.isArray(list)
@@ -171,12 +174,14 @@ function ChatPage() {
             if (open) convId = open.id;
           }
         } catch {
+          if (stale) return;
           setError("Failed to load conversations.");
         }
       }
 
       if (!convId) {
         await fetchConversations();
+        if (stale) return;
         setLoadingConv(false);
         setConversation(null);
         return;
@@ -187,6 +192,7 @@ function ChatPage() {
         fetchMessages(convId),
         fetchConversations(),
       ]);
+      if (stale) return;
       setLoadingConv(false);
       startPolling(convId);
     }
@@ -194,6 +200,7 @@ function ChatPage() {
     init();
 
     return () => {
+      stale = true;
       if (pollRef.current) clearInterval(pollRef.current);
     };
   }, [token, authLoading, conversationIdParam, fetchConversation, fetchMessages, startPolling, fetchConversations]);