feat: Initial commit

lib/shared_pref_singleton.dart

@@ -0,0 +1,22 @@
+import 'package:shared_preferences/shared_preferences.dart';
+
+class SharedPrefSingleton {
+  static final SharedPrefSingleton _instance = SharedPrefSingleton._internal();
+  factory SharedPrefSingleton() => _instance;
+  SharedPrefSingleton._internal();
+  late SharedPreferences _pref;
+  Future<void> initialize() async {
+    _pref = await SharedPreferences.getInstance();
+  }
+
+  Future<bool> setAutoFirewall(bool ok) => _pref.setBool("auto_firewall", ok);
+  bool get autoFirewall => _pref.getBool("auto_firewall") ?? true;
+
+  Future<bool> setAppTheme(bool ok) => _pref.setBool("app_theme", ok);
+  // false = dark, true = light
+  bool get appTheme => _pref.getBool("app_theme") ?? false;
+
+  Future<bool> setSavedConnection(String config) =>
+      _pref.setString("saved_connection", config);
+  String get savedConnection => _pref.getString("saved_connection") ?? "[]";
+}