feat(client): 断开连接前弹二次确认框(避免误触瞬断)

连接键在 on 态点击不再直接断开:先弹危险操作确认框(告知连接已加密,
确认才 toggle 断开);off/connecting 态行为不变直接 toggle。
新增 l10n disconnectTitle/Body/Action(en/zh/es/ja/ko/ru 六语)。

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FEVUXAbFT6bF1Qw27RHWoD

client/lib/l10n/app_text.dart

@@ -343,6 +343,9 @@ abstract class AppText {
   String get capOn;
   String get connectNow; // 连接键 off 态圆内文字
   String get secure; // 连接键圆内「已加密」
+  String get disconnectTitle; // 断开确认弹窗标题
+  String get disconnectBody; // 断开确认弹窗正文
+  String get disconnectAction; // 断开确认弹窗「断开」按钮
 
   // ── 底部 / 侧栏导航 ──
   String get tabConnect;

client/lib/l10n/strings_en.dart

@@ -27,6 +27,12 @@ class StringsEn extends AppText {
   @override
   String get secure => 'SECURE';
   @override
+  String get disconnectTitle => 'Disconnect?';
+  @override
+  String get disconnectBody => 'Your connection is encrypted. Are you sure you want to disconnect?';
+  @override
+  String get disconnectAction => 'Disconnect';
+  @override
   String get tabConnect => 'Connect';
   @override
   String get tabServers => 'Servers';

client/lib/l10n/strings_es.dart

@@ -27,6 +27,12 @@ class StringsEs extends AppText {
   @override
   String get secure => 'SEGURO';
   @override
+  String get disconnectTitle => '¿Desconectar?';
+  @override
+  String get disconnectBody => 'Tu conexión está cifrada. ¿Seguro que quieres desconectar?';
+  @override
+  String get disconnectAction => 'Desconectar';
+  @override
   String get tabConnect => 'Conectar';
   @override
   String get tabServers => 'Servidores';

client/lib/l10n/strings_ja.dart

@@ -27,6 +27,12 @@ class StringsJa extends AppText {
   @override
   String get secure => 'セキュア';
   @override
+  String get disconnectTitle => '切断しますか?';
+  @override
+  String get disconnectBody => '接続は暗号化されています。切断してもよろしいですか?';
+  @override
+  String get disconnectAction => '切断';
+  @override
   String get tabConnect => '接続';
   @override
   String get tabServers => 'サーバー';

client/lib/l10n/strings_ko.dart

@@ -27,6 +27,12 @@ class StringsKo extends AppText {
   @override
   String get secure => '보안';
   @override
+  String get disconnectTitle => '연결 해제하시겠습니까?';
+  @override
+  String get disconnectBody => '연결이 암호화되어 있습니다. 정말 연결을 해제하시겠습니까?';
+  @override
+  String get disconnectAction => '연결 해제';
+  @override
   String get tabConnect => '연결';
   @override
   String get tabServers => '서버';

client/lib/l10n/strings_ru.dart

@@ -27,6 +27,12 @@ class StringsRu extends AppText {
   @override
   String get secure => 'ЗАЩИЩЕНО';
   @override
+  String get disconnectTitle => 'Отключиться?';
+  @override
+  String get disconnectBody => 'Ваше соединение зашифровано. Действительно отключиться?';
+  @override
+  String get disconnectAction => 'Отключить';
+  @override
   String get tabConnect => 'Подключение';
   @override
   String get tabServers => 'Серверы';

client/lib/l10n/strings_zh.dart

@@ -27,6 +27,12 @@ class StringsZh extends AppText {
   @override
   String get secure => '已加密';
   @override
+  String get disconnectTitle => '断开连接?';
+  @override
+  String get disconnectBody => '当前连接已加密。确定要断开吗?';
+  @override
+  String get disconnectAction => '断开';
+  @override
   String get tabConnect => '连接';
   @override
   String get tabServers => '节点';

client/lib/screens/connect_page.dart

@@ -21,6 +21,47 @@ class ConnectPage extends ConsumerWidget {
   final bool isWide;
   final VoidCallback onOpenNodes;
 
+  // 连接键点击:off/connecting 直接 toggle;on 态(已连接)先弹二次确认再断开,
+  // 避免误触瞬断加密连接。
+  Future<void> _handleToggle(BuildContext context, WidgetRef ref, VpnPhase phase, AppText t) async {
+    final notifier = ref.read(connectionProvider.notifier);
+    if (phase != VpnPhase.on) {
+      notifier.toggle();
+      return;
+    }
+    final c = context.pangolin;
+    final ok = await showDialog<bool>(
+      context: context,
+      builder: (ctx) => AlertDialog(
+        backgroundColor: c.surface,
+        shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(PangolinRadius.xl)),
+        title: Row(children: [
+          Container(
+              width: 34,
+              height: 34,
+              decoration: BoxDecoration(color: c.dangerSubtle, shape: BoxShape.circle),
+              child: Icon(PangolinIcons.alertTriangle, size: 18, color: c.danger)),
+          const SizedBox(width: 12),
+          Expanded(
+              child: Text(t.disconnectTitle,
+                  overflow: TextOverflow.ellipsis,
+                  style: PangolinText.body.copyWith(color: c.fg1, fontWeight: FontWeight.w700))),
+        ]),
+        content: Text(t.disconnectBody, style: PangolinText.sm.copyWith(color: c.fg2, height: 1.5)),
+        actions: [
+          TextButton(
+              onPressed: () => Navigator.pop(ctx, false),
+              child: Text(t.devCancel, style: PangolinText.sm.copyWith(color: c.fg2, fontWeight: FontWeight.w600))),
+          TextButton(
+              onPressed: () => Navigator.pop(ctx, true),
+              child: Text(t.disconnectAction,
+                  style: PangolinText.sm.copyWith(color: c.danger, fontWeight: FontWeight.w700))),
+        ],
+      ),
+    );
+    if (ok == true) notifier.toggle();
+  }
+
   @override
   Widget build(BuildContext context, WidgetRef ref) {
     final c = context.pangolin;
@@ -53,7 +94,7 @@ class ConnectPage extends ConsumerWidget {
       elapsed: conn.elapsed,
       offLabel: t.connectNow,
       secureLabel: t.secure,
-      onTap: () => ref.read(connectionProvider.notifier).toggle(),
+      onTap: () => _handleToggle(context, ref, conn.phase, t),
     );
 
     final captionWidget = Column(mainAxisSize: MainAxisSize.min, children: [
@@ -94,7 +135,7 @@ class ConnectPage extends ConsumerWidget {
               offLabel: t.connectNow,
               secureLabel: t.secure,
               size: 176,
-              onTap: () => ref.read(connectionProvider.notifier).toggle(),
+              onTap: () => _handleToggle(context, ref, conn.phase, t),
             ),
             const SizedBox(height: 24),
             Text(caption,