fix(translation): 仅在蓝牙设备已连接时启用面对面翻译模式

lib/modules/translation/views/translation_view.dart

@@ -1102,11 +1102,13 @@ class TranslationView extends GetView<TranslationController> {
                 'faceToFaceTranslation'.tr,
                 Icons.people,
                 Colors.green,
-                onTap: () async {
+                onTap: controller.bluetoothManager.currentDevice != null
+                    ? () async {
                         Get.back();
                         await controller.changeTranslationMode('faceToFace');
                         controller.startRecognition();
-                },
+                      }
+                    : null,
               ),
               _buildModeItem(
                 context,