docs: private void offerHandler(Channel channel, RemotingCommand request) {
          AbstractRemotingCommandBody commandBody = request.getBody();
          String nodeGroup = commandBody.getNodeGroup();
          String identity = commandBody.getIdentity();
          NodeType nodeType = NodeType.valueOf(commandBody.getNodeType());
  
          // 1. 将 channel 纳入管理中(不存在就加入)
          appContext.getChannelManager().offerChannel(new ChannelWrapper(channel, nodeType, nodeGroup, identity));
      }