update lcemp networking

Minecraft.World/x64headers/extraX64.h

@@ -249,6 +249,9 @@ private:
 };
 
 void Win64_SetupRemoteQNetPlayer(IQNetPlayer *player, BYTE smallId, bool isHost, bool isLocal);
+char GetUsername();
+PlayerUID Win64_UsernameToXuid(const char* username);
+PlayerUID Win64_UsernameToXuid(const wchar_t* username);
 
 const int QNET_GETSENDQUEUESIZE_SECONDARY_TYPE = 0;
 const int QNET_GETSENDQUEUESIZE_MESSAGES = 0;