refactor: create MainMenu and GameMenu classes

include/render/gui/GameMenu.h

@@ -0,0 +1,24 @@
+#pragma once
+
+#include "SummonMenu.h"
+
+namespace td {
+namespace gui {
+
+class GameMenu : public GuiWidget {
+private:
+    std::unique_ptr<SummonMenu> m_SummonMenu;
+public:
+    GameMenu(client::Client* client);
+
+    virtual void render();
+private:
+    void showTPS();
+    void showStats();
+    void showPlayers();
+    void showLobbyProgress();
+    void showTeamSelection();
+};
+
+} // namespace gui
+} // namespace td