Core/Networking: Fixed Socket::DelayedCloseSocket not working if write queue is empty when its called on linux and mac

Closes #29887

src/server/game/Server/WorldSocket.cpp

@@ -724,6 +724,7 @@ void WorldSocket::HandleAuthSessionCallback(std::shared_ptr<WorldPackets::Auth::
     // Check that Key and account name are the same on client and server
     if (memcmp(hmac.GetDigest().data(), authSession->Digest.data(), authSession->Digest.size()) != 0)
     {
+        SendAuthResponseError(ERROR_DENIED);
         TC_LOG_ERROR("network", "WorldSocket::HandleAuthSession: Authentication failed for account: {} ('{}') address: {}", account.Game.Id, authSession->RealmJoinTicket, address);
         DelayedCloseSocket();
         return;

src/server/shared/Networking/Socket.h

@@ -164,7 +164,14 @@ public:
     }
 
     /// Marks the socket for closing after write buffer becomes empty
-    void DelayedCloseSocket() { _closing = true; }
+    void DelayedCloseSocket()
+    {
+        if (_closing.exchange(true))
+            return;
+
+        if (_writeQueue.empty())
+            CloseSocket();
+    }
 
     MessageBuffer& GetReadBuffer() { return _readBuffer; }