"New C++ Class" dialog: More options and better guidance for QML integration, than just "Add QML_ELEMENT"

Currently, the dialog only provides "Add QML_ELEMENT", which creates an instantiable QML type that's named after the C++ class.

However, there are many other possibilities:

• https://doc.qt.io/qt-6/qtqml-cppintegration-overview.html#choosing-the-correct-integration-method-between-c-and-qml
• https://doc.qt.io/qt-6/qtqml-cppintegration-definetypes.html#registering-c-types-with-the-qml-type-system

It would be helpful for the dialog to provide more common options, as well as to prevent users from selecting invalid combinations, e.g.

• A class with QML_ELEMENT must also have Q_OBJECT
• A class with QML_VALUE_TYPE must also have Q_GADGET
• QML_ELEMENT and QML_ANONYMOUS are mutually exclusive