CategoryModel: Switch rootCategories property to its actual type
In Qt 6 QML there seem to be no need for QVariantList hacks to transfer lists of registered metaobjects to QML.
Also port methods to return const references to avoid unneeded copies.
In Qt 6 QML there seem to be no need for QVariantList hacks to transfer lists of registered metaobjects to QML.
Also port methods to return const references to avoid unneeded copies.