prevent GameSend send() call on invalid socket (#240)

prevents WSAENOTSOCK by not allowing a `send()` call on an
invalid/closed socket when the game client isn't connected

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src/Network/GlobalHandler.cpp

@@ -51,6 +51,10 @@ int KillSocket(uint64_t Dead) {
 }
 
 void GameSend(std::string_view Data) {
+    if (!GConnected) {
+        debug("Tried to call GameSend but socket was not connected. Data: " + std::string(Data));
+        return;
+    }
     static std::mutex Lock;
     std::scoped_lock Guard(Lock);
     auto ToSend = Utils::PrependHeader<std::string_view>(Data);