feat(remote): 修复键盘输入映射并重构连接流程

- Android端注入按键时显式设置SOURCE_KEYBOARD，修复IME丢弃事件导致输入框无法输入文字的问题
- Flutter端新增Flutter逻辑键到Android keyCode的转换映射，避免功能键误触发
- 重构RemoteController，分离信令连接与远程控制逻辑，支持设备列表选择与配对码兑换
- AuthRepository接口新增getBindings、getOnlineDevices、redeemPairingCode方法
- DioAuthRepository实现401自动刷新token重试机制
- ConnectionSessionState扩展设备列表、在线状态、配对码等状态字段

webrtc_controller_flutter/lib/features/auth/data/dio_auth_repository.dart

@@ -6,6 +6,7 @@ import '../../../app/constants/app_constants.dart';
 import '../../../core/network/api_exception.dart';
 import '../../../core/storage/token_storage.dart';
 import '../domain/auth_repository.dart';
+import '../../connection/domain/binding_device.dart';
 
 /// 基于 Dio 的 [AuthRepository] 实现。
 class DioAuthRepository implements AuthRepository {
@@ -101,13 +102,41 @@ class DioAuthRepository implements AuthRepository {
   Future<Map<String, dynamic>> verify() => _get('/api/client/verify');
 
   @override
-  Future<Map<String, dynamic>> bindings() => _get('/api/client/bindings');
+  Future<List<BindingDevice>> getBindings() async {
+    final data = await _get('/api/client/bindings');
+    final list = (data['bindings'] as List?) ?? [];
+    return [
+      for (final e in list)
+        if (e is Map)
+          BindingDevice.fromJson(e.cast<String, dynamic>()),
+    ];
+  }
+
+  @override
+  Future<List<BindingDevice>> getOnlineDevices() async {
+    final data = await _get('/api/client/devices/online');
+    final list = (data['devices'] as List?) ?? [];
+    return [
+      for (final e in list)
+        if (e is Map)
+          BindingDevice.fromJson(e.cast<String, dynamic>()),
+    ];
+  }
+
+  @override
+  Future<void> redeemPairingCode(String code) async {
+    await _post(
+      '/api/client/pairing/redeem',
+      body: {'code': code},
+      auth: true,
+    );
+  }
 
   @override
   Future<Map<String, dynamic>?> turnCredentials() async {
     try {
       return await _get('/api/client/turn-credentials');
-    } on ApiException {
+    } on Object {
       return null;
     }
   }
@@ -121,24 +150,61 @@ class DioAuthRepository implements AuthRepository {
   Future<Map<String, dynamic>> _post(
     String path, {
     required Map<String, dynamic> body,
+    bool auth = false,
   }) async {
-    final res = await _dio.post<dynamic>(
-      path,
-      data: jsonEncode(body),
+    return _handle(
+      await _send(
+        () => _dio.post<dynamic>(
+          path,
+          data: jsonEncode(body),
+          options: Options(
+            headers: {
+              if (auth && _accessToken != null)
+                'Authorization': 'Bearer $_accessToken',
+            },
+          ),
+        ),
+      ),
     );
-    return _handle(res);
   }
 
   Future<Map<String, dynamic>> _get(String path) async {
-    final res = await _dio.get<dynamic>(
-      path,
-      options: Options(
-        headers: {
-          if (_accessToken != null) 'Authorization': 'Bearer $_accessToken',
-        },
+    return _handle(
+      await _send(
+        () => _dio.get<dynamic>(
+          path,
+          options: Options(
+            headers: {
+              if (_accessToken != null)
+                'Authorization': 'Bearer $_accessToken',
+            },
+          ),
+        ),
       ),
     );
-    return _handle(res);
+  }
+
+  /// 发送请求，遇 401 时尝试用 refreshToken 续期后重试一次。
+  ///
+  /// Dio 默认对非 2xx 直接抛出 [DioException]（bad response），不会走到
+  /// [_handle]，因此在异常层拦截 401 并触发刷新重试，避免已登录用户因
+  /// accessToken 过期而直接失败。
+  Future<Response<dynamic>> _send(
+    Future<Response<dynamic>> Function() request,
+  ) async {
+    try {
+      return await request();
+    } on DioException catch (e) {
+      if (e.response?.statusCode == 401 && await hasRefreshToken()) {
+        try {
+          await refresh();
+        } on Object {
+          rethrow;
+        }
+        return await request();
+      }
+      rethrow;
+    }
   }
 
   Map<String, dynamic> _handle(Response<dynamic> res) {

webrtc_controller_flutter/lib/features/auth/domain/auth_repository.dart

@@ -1,3 +1,5 @@
+import '../../connection/domain/binding_device.dart';
+
 /// 账号体系与自助接口抽象（对应服务端 /api/auth/* 与 /api/client/*）。
 abstract interface class AuthRepository {
   /// 内存中的 accessToken（掉线即失）。
@@ -19,7 +21,14 @@ abstract interface class AuthRepository {
 
   Future<Map<String, dynamic>> verify();
 
-  Future<Map<String, dynamic>> bindings();
+  /// 获取主控端已绑定的被控设备列表（含名称、鉴权方式等）。
+  Future<List<BindingDevice>> getBindings();
+
+  /// 获取已绑定且当前在线（信令网络活跃）的设备列表。
+  Future<List<BindingDevice>> getOnlineDevices();
+
+  /// 使用被控端展示的一次性配对码建立绑定关系。
+  Future<void> redeemPairingCode(String code);
 
   /// 拉取 TURN 短期凭证（服务端开启时返回 iceServers）；关闭时返回 null。
   Future<Map<String, dynamic>?> turnCredentials();