fix language selection and missing locales

src/App.jsx

@@ -1,5 +1,7 @@
+import { useEffect } from 'react';
 import { Routes, Route, Navigate } from 'react-router-dom';
 import { useAuth } from './contexts/AuthContext';
+import { useLanguage } from './contexts/LanguageContext';
 import Layout from './components/Layout';
 import ProtectedRoute from './components/ProtectedRoute';
 import Home from './pages/Home';
@@ -13,6 +15,14 @@ import GuestJoin from './pages/GuestJoin';
 
 export default function App() {
   const { user, loading } = useAuth();
+  const { setLanguage } = useLanguage();
+
+  // Sync language from server when user loads
+  useEffect(() => {
+    if (user?.language) {
+      setLanguage(user.language);
+    }
+  }, [user?.language, setLanguage]);
 
   if (loading) {
     return (