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

lib/main.dart

@@ -1,7 +1,7 @@
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
-import 'package:hiddify/bootstrap.dart';
-import 'package:hiddify/core/model/environment.dart';
+import 'package:umbrix/bootstrap.dart';
+import 'package:umbrix/core/model/environment.dart';
 
 void main() async {
   final widgetsBinding = WidgetsFlutterBinding.ensureInitialized();