Accept Qt.RightButton on the HomeScreenPages and FavouritesBar
MouseAreas and open the settings view (wallpaper/widgets) on
right-click, mirroring the existing long-press behavior for mouse
users.
This refactors the homescreen state object to isolate drag & drop from
swipe states, allowing for using proper system-level drag & drop for delegate
movement. This then ports the new applet list to use it.
This converts many of the animation durations to Kirigami units so that
they can be controlled system wide. It also speeds up several of the
animation durations (ex. in folio) from 800ms to 400ms to improve the
feel and responsiveness of the shell.
