i8n과 광고 수정

lib/routes/app_routes.dart

@@ -9,6 +9,7 @@ import 'package:submanager/screens/splash_screen.dart';
 import 'package:submanager/screens/sms_permission_screen.dart';
 import 'package:submanager/models/subscription_model.dart';
 import 'package:submanager/screens/payment_card_management_screen.dart';
+import '../l10n/app_localizations.dart';
 
 class AppRoutes {
   static const String splash = '/splash';
@@ -81,9 +82,9 @@ class AppRoutes {
 
   static Route<dynamic> _errorRoute() {
     return MaterialPageRoute(
-      builder: (_) => const Scaffold(
+      builder: (context) => Scaffold(
         body: Center(
-          child: Text('페이지를 찾을 수 없습니다'),
+          child: Text(AppLocalizations.of(context).pageNotFound),
         ),
       ),
     );