Refactor Steam Networking Components

- Removed SteamMessageHandler class and its implementation files.
- Integrated control packet handling directly into the SteamMessageHandler.
- Updated TCPClient and TCPServer classes to improve connection management and error handling.
- Added SteamNetworkingManager class to manage Steam networking, including lobby creation and connection handling.
- Implemented callbacks for Steam Friends and Matchmaking to handle lobby events.
- Enhanced message forwarding logic between TCP clients and Steam connections.
- Introduced control packet handling for ping responses.
- Improved thread safety with mutexes for shared resources.

steamnet/control_packets.h

@@ -0,0 +1,8 @@
+#ifndef CONTROL_PACKETS_H
+#define CONTROL_PACKETS_H
+
+#include <steamnetworkingtypes.h>
+
+void handleControlPacket(const char* data, size_t size, HSteamNetConnection conn);
+
+#endif // CONTROL_PACKETS_H