fix: bug with showing user information and enhance authentication and user display features

- Updated LoginForm to store a complete authentication structure in localStorage, improving user session management.
- Added user type display in ChatSidebar to differentiate between local and OAuth users.
- Refactored Chat component to handle user initialization more robustly, ensuring proper navigation and state management during authentication.

Author: asdek

frontend/src/features/authentication/LoginForm.tsx

@@ -233,7 +233,25 @@ const LoginForm = ({ providers, returnUrl = '/chat/new' }: LoginFormProps) => {
                 ...user,
                 password_change_required: false,
             };
-            localStorage.setItem('auth', JSON.stringify(updatedUser));
+
+            // Get current auth data
+            const currentAuth = localStorage.getItem('auth');
+            let authData;
+            try {
+                authData = currentAuth ? JSON.parse(currentAuth) : null;
+            } catch {
+                authData = null;
+            }
+
+            // Create a full authentication info structure
+            const updatedAuthData = {
+                type: 'user',
+                user: updatedUser,
+                providers: authData?.providers || [],
+            };
+
+            // Always store the complete auth structure
+            localStorage.setItem('auth', JSON.stringify(updatedAuthData));
             navigate(returnUrl);
         }
     };

frontend/src/features/chat/ChatSidebar.tsx

@@ -352,6 +352,9 @@ const ChatSidebar = ({
                                         <div className="grid flex-1 text-left text-sm leading-tight">
                                             <span className="truncate font-semibold">{user?.name}</span>
                                             <span className="truncate text-xs">{user?.mail}</span>
+                                            <span className="truncate text-xs text-muted-foreground">
+                                                {user?.type === 'local' ? 'local' : 'oauth'}
+                                            </span>
                                         </div>
                                     </div>
                                 </DropdownMenuLabel>

frontend/src/pages/Chat.tsx

@@ -68,10 +68,9 @@ const Chat = () => {
     const [selectedProvider, setSelectedProvider] = useState<string | null>(null);
     const [user, setUser] = useState<User | null>(null);
     const { isDesktop } = useBreakpoint();
-    const needsUserUpdateRef = useRef(false);
     const needsProviderUpdateRef = useRef(true);
-    const userDataRef = useRef<User | null>(null);
     const previousFlowIdRef = useRef(flowId);
+    const userInitialized = useRef(false);
 
     // Check if provider needs initialization or update when:
     // 1. We have no selected provider yet (first login)
@@ -125,28 +124,27 @@ const Chat = () => {
             return;
         }
 
-        const user = JSON.parse(auth)?.user;
-
-        if (!user) {
-            // Save current path for redirect after login
-            const currentPath = window.location.pathname;
-            // Only save if it's not the default route
-            const returnParam = currentPath !== '/chat/new' ? `?returnUrl=${encodeURIComponent(currentPath)}` : '';
-            navigate(`/login${returnParam}`);
-            return;
+        try {
+            const authData = JSON.parse(auth);
+            const user = authData?.user;
+
+            if (!user) {
+                // Save current path for redirect after login
+                const currentPath = window.location.pathname;
+                // Only save if it's not the default route
+                const returnParam = currentPath !== '/chat/new' ? `?returnUrl=${encodeURIComponent(currentPath)}` : '';
+                navigate(`/login${returnParam}`);
+                return;
+            } else {
+                userInitialized.current = true;
+                window.requestAnimationFrame(() => setUser(user));
+            }
+        } catch {
+            // If we have a parse error, redirect to login
+            navigate('/login');
         }
-
-        needsUserUpdateRef.current = true;
-        userDataRef.current = user;
     }, [navigate]);
 
-    useLayoutEffect(() => {
-        if (needsUserUpdateRef.current && userDataRef.current) {
-            needsUserUpdateRef.current = false;
-            setUser(userDataRef.current);
-        }
-    }, []);
-
     // Handle provider selection changes
     const handleProviderChange = (provider: string) => {
         setSelectedProvider(provider);