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

steam/steam_utils.cpp

@@ -0,0 +1,13 @@
+#include "steam_utils.h"
+#include <iostream>
+
+std::vector<std::pair<CSteamID, std::string>> SteamUtils::getFriendsList() {
+    std::vector<std::pair<CSteamID, std::string>> friendsList;
+    int friendCount = SteamFriends()->GetFriendCount(k_EFriendFlagAll);
+    for (int i = 0; i < friendCount; ++i) {
+        CSteamID friendID = SteamFriends()->GetFriendByIndex(i, k_EFriendFlagAll);
+        const char* name = SteamFriends()->GetFriendPersonaName(friendID);
+        friendsList.push_back({friendID, name});
+    }
+    return friendsList;
+}