feat: 控制指令消息改为protobuf二进制

webrtc_controller_flutter/lib/webrtc/webrtc_controller.dart

@@ -3,6 +3,7 @@ import 'package:flutter_webrtc/flutter_webrtc.dart';
 
 import '../config/ice_servers.dart';
 import '../models/signal_message.dart';
+import '../proto/control_message.pb.dart';
 import '../signaling/signaling_client.dart';
 
 /// 封装 WebRTC 连接逻辑（对应 Android 端 WebRtcClient）。
@@ -105,8 +106,19 @@ class WebRtcController {
   void _setupDataChannel(RTCDataChannel channel) {
     channel.onMessage = (RTCDataChannelMessage message) {
       // 处理来自被控端的消息（本控制端主要发送，此处仅做日志记录）。
-      // ignore: avoid_print
-      print('DataChannel message: ${message.text}');
+      if (message.isBinary) {
+        try {
+          final command = ControlMessage.fromBuffer(message.binary);
+          // ignore: avoid_print
+          print('DataChannel message: ${command.action}');
+        } catch (e) {
+          // ignore: avoid_print
+          print('DataChannel message decode failed: $e');
+        }
+      } else {
+        // ignore: avoid_print
+        print('DataChannel text message: ${message.text}');
+      }
     };
     channel.onDataChannelState = (RTCDataChannelState state) {
       // ignore: avoid_print
@@ -171,11 +183,11 @@ class WebRtcController {
     await _pc?.addCandidate(candidate);
   }
 
-  /// 通过 DataChannel 发送控制指令（JSON 字符串）。
-  void sendControlCommand(String commandJson) {
+  /// 通过 DataChannel 发送控制指令（protobuf 二进制）。
+  void sendControlCommand(ControlMessage command) {
     if (_dataChannel?.state == RTCDataChannelState.RTCDataChannelOpen) {
-      debugPrint('WebRtcController: Sending command -> $commandJson');
-      _dataChannel!.send(RTCDataChannelMessage(commandJson));
+      debugPrint('WebRtcController: Sending command -> ${command.action}');
+      _dataChannel!.send(RTCDataChannelMessage.fromBinary(command.writeToBuffer()));
     }
   }