fix(auth): useLogin maps login response to User, ProtectedRoute calls useAuth()

frontend/src/routes/ProtectedRoute.tsx

@@ -1,11 +1,15 @@
 import React from 'react';
 import { Navigate, useLocation } from 'react-router-dom';
 import { useAuthStore } from '@/store/authStore';
+import { useAuth } from '@/hooks/useAuth';
 
 export function ProtectedRoute({ children }: { children: React.ReactNode }) {
   const { isAuthenticated } = useAuthStore();
   const location = useLocation();
 
+  // Load user data on mount (handles page refresh)
+  useAuth();
+
   if (!isAuthenticated) {
     return <Navigate to="/login" state={{ from: location }} replace />;
   }