fix(netty): 修复设备心跳和离线处理逻辑

- 将心跳间隔从60秒调整为30秒
- 修复平台ID设置顺序问题，确保context正确初始化
- 优化在线处理逻辑，支持重复连接时替换旧通道
- 更新离线方法签名，传入通道参数进行精确匹配
- 添加通道比较逻辑，避免错误的离线操作

netty-client/src/main/java/com/sv/netty/ClientInitializer.java

@@ -12,7 +12,7 @@ import io.netty.handler.timeout.IdleStateHandler;
 
 public class ClientInitializer extends ChannelInitializer<SocketChannel> {
 
-    private final static int TIME_HEART_BEAT = 60;
+    private final static int TIME_HEART_BEAT = 30;
 
     public ClientThread.ReConnectHandler reConnectHandler;
     public ClientHandler dmClientHandler;