Add debug logging for session changes

src/App.tsx

@@ -19,13 +19,21 @@ import { PendingValidationView } from './components/PendingValidationView';
 export default function App() {
   const [session, setSession] = useState<AuthSession | null>(() => getStoredSession());
 
+  useEffect(() => {
+    console.log('[App] session changed:', session ? 'logged in' : 'logged out');
+  }, [session]);
+
   const handleSignOut = () => {
     signOut();
     setSession(null);
   };
 
   if (!session) {
-    return <LoginPage onLogin={() => setSession(getStoredSession())} />;
+    return <LoginPage onLogin={() => {
+      const stored = getStoredSession();
+      console.log('[App] onLogin, stored session:', stored ? 'found' : 'null');
+      setSession(stored);
+    }} />;
   }
 
   const [appState, setAppState] = useState<AppState>({