feat: mobile-like window size and always-visible stats

- Changed window size to mobile phone format (400x800)
- Removed width condition for ActiveProxyFooter - now always visible
- Added run-umbrix.sh launch script with icon copying
- Stats cards now display on all screen sizes

test/core/database/migrations_test.dart

@@ -1,6 +1,6 @@
 import 'package:drift_dev/api/migrations.dart';
 import 'package:flutter_test/flutter_test.dart';
-import 'package:hiddify/core/database/app_database.dart';
+import 'package:umbrix/core/database/app_database.dart';
 
 import 'generated_migrations/schema.dart';