feat(contacts): имена из телефонной книги везде + тумблер в дев-меню

lib/core/config/app_phonebook_names.dart

@@ -0,0 +1,23 @@
+import 'package:flutter/foundation.dart';
+
+import 'persisted_setting.dart';
+
+class AppPhonebookNames {
+  static const prefKey = 'dev_phonebook_names';
+  static const bool defaultValue = true;
+
+  static final _setting = PersistedSetting<bool>(
+    prefKey: prefKey,
+    defaultValue: defaultValue,
+    read: (prefs, key) => prefs.getBool(key),
+    write: (prefs, key, value) async {
+      await prefs.setBool(key, value);
+    },
+  );
+
+  static ValueNotifier<bool> get current => _setting.current;
+
+  static Future<bool> load() => _setting.load();
+
+  static Future<void> save(bool value) => _setting.save(value);
+}