重构Steam网络管理，整合房间管理功能，添加多路复用支持，优化TCP服务器和消息处理

multiplex/multiplex_manager.h

@@ -0,0 +1,33 @@
+#pragma once
+
+#include <unordered_map>
+#include <memory>
+#include <mutex>
+#include <vector>
+#include <boost/asio.hpp>
+#include <steam_api.h>
+#include <isteamnetworkingsockets.h>
+#include <steamnetworkingtypes.h>
+
+using boost::asio::ip::tcp;
+
+class MultiplexManager {
+public:
+    MultiplexManager(ISteamNetworkingSockets* steamInterface, HSteamNetConnection steamConn);
+    ~MultiplexManager();
+
+    uint32_t addClient(std::shared_ptr<tcp::socket> socket);
+    void removeClient(uint32_t id);
+    std::shared_ptr<tcp::socket> getClient(uint32_t id);
+
+    void sendTunnelPacket(uint32_t id, const char* data, size_t len, int type);
+
+    void handleTunnelPacket(const char* data, size_t len);
+
+private:
+    ISteamNetworkingSockets* steamInterface_;
+    HSteamNetConnection steamConn_;
+    std::unordered_map<uint32_t, std::shared_ptr<tcp::socket>> clientMap_;
+    std::mutex mapMutex_;
+    uint32_t nextId_;
+};