refactoring and clean up of chat cliet

packages/chat-client/src/hooks/useSession.js

@@ -9,18 +9,27 @@ export function useSession() {
   const [loadingHistory, setLoadingHistory] = useState(false);
   const [error, setError] = useState(null);
 
-  // Load session list on mount
-  useEffect(() => {
-    loadSessions();
-  }, []);
 
-  async function loadSessions() {
+    // Called by useChat after a message completes — keeps session list fresh
+  const refreshSessions = useCallback(async () => {
     try {
       const data = await fetchSessions();
       setSessions(data);
-    } catch (err) {
-      setError(err.message);
+    } catch {
+      // non-critical — sidebar just won't update
     }
+  }, []);
+
+  // Load session list on mount
+  useEffect(() => {
+    refreshSessions();
+  }, [refreshSessions]);
+
+  function episodesToMessages(episodes) {
+      return [...episodes].reverse().flatMap(ep => [
+          { id: `${ep.id}-user`, role: 'user',      text: ep.user_message },
+          { id: `${ep.id}-ai`,   role: 'assistant', text: ep.ai_response  },
+      ]);
   }
 
   // Switch to an existing session and load its history
@@ -32,10 +41,7 @@ export function useSession() {
     try {
       const data = await fetchSessionHistory(session.external_id);
       // History comes back newest-first — reverse for display
-      const history = data.episodes.reverse().map(ep => ([
-        { id: `${ep.id}-user`, role: 'user',      text: ep.user_message },
-        { id: `${ep.id}-ai`,   role: 'assistant', text: ep.ai_response  },
-      ])).flat();
+      const history = episodesToMessages(data.episodes);
 
       setMessages(history);
     } catch (err) {
@@ -58,15 +64,7 @@ export function useSession() {
     setMessages([]);
   }, []);
 
-  // Called by useChat after a message completes — keeps session list fresh
-  const refreshSessions = useCallback(async () => {
-    try {
-      const data = await fetchSessions();
-      setSessions(data);
-    } catch {
-      // non-critical — sidebar just won't update
-    }
-  }, []);
+
 
   // Append a message to the current thread (used by useChat)
   const appendMessage = useCallback((message) => {