fix #15473: Register AppMenuModel as PlatformAppMenuModel on macOS

Using AppMenuModel for GUI menu bar and PlatformAppMenuModel for platform menu bar makes more sense when both menu bar types are possible on a platform

Author: adazem009

src/appshell/appshellmodule.cpp

@@ -163,7 +163,7 @@ void AppShellModule::registerUiTypes()
     qmlRegisterType<CommonAudioApiConfigurationModel>("MuseScore.Preferences", 1, 0, "CommonAudioApiConfigurationModel");
 
 #if defined(Q_OS_MACOS)
-    qmlRegisterType<AppMenuModel>("MuseScore.AppShell", 1, 0, "AppMenuModel");
+    qmlRegisterType<AppMenuModel>("MuseScore.AppShell", 1, 0, "PlatformAppMenuModel");
 #elif defined(Q_OS_LINUX)
     qmlRegisterType<AppMenuModel>("MuseScore.AppShell", 1, 0, "PlatformAppMenuModel");
     qmlRegisterType<NavigableAppMenuModel>("MuseScore.AppShell", 1, 0, "AppMenuModel");