citra_qt: Add Game List configuration

This adds a Game List configuration group box which is similar to yuzu's, with features including icon size setting, row 1/2 text, and ability to hide invalid titles (those without a valid SMDH). I also added a UI tab and moved the language and theme settings there.

src/citra_qt/main.cpp

@@ -1257,6 +1257,7 @@ void GMainWindow::OnConfigure() {
             SetDiscordEnabled(UISettings::values.enable_discord_presence);
         emit UpdateThemedIcons();
         SyncMenuUISettings();
+        game_list->RefreshGameDirectory();
         config->Save();
     }
 }