kquickcontrols/KeySequenceItem: Add support for setting KKeySequenceRecorder pattern

modifierlessAllowed and modifierOnlyAllowed were deprecated in 6.12 and it is now preferred to use pattern. This is a set of flags, so we have to expose the values in KQuickControls as ShortcutPattern.

e.g:

KQuickControls.KeySequenceItem {
    patterns: KQuickControls.ShortcutPattern.Modifier
}