Merge branch 'improvements' of https://github.com/777genius/claude_agent_teams_ui into improvements

src/renderer/components/team/activity/ActivityTimeline.tsx

@@ -44,11 +44,8 @@ const MessageRowWithObserver = ({
 
   useEffect(() => {
     messageRef.current = message;
-  }, [message]);
-
-  useEffect(() => {
     onVisibleRef.current = onVisible;
-  }, [onVisible]);
+  }, [message, onVisible]);
 
   useEffect(() => {
     if (!onVisible) return;

src/renderer/hooks/useTeamMessagesRead.ts

@@ -27,5 +27,6 @@ export function useTeamMessagesRead(teamName: string): {
     [teamName]
   );
 
-  return { readSet, markRead };
+  const effectiveReadSet = !teamName ? new Set<string>() : readSet;
+  return { readSet: effectiveReadSet, markRead };
 }