Distinguish between touch and mouse to pan the Flickable

Currently, Flickable::interactive means that you can pan it with the mouse press and drag. It is always possible to pan it with the mouse wheel. We should in fact make sure that you can always pan it with touch event even when interactive is false.

perhaps interactive property should be deprecated and renamed something like pan-with-mouse. Alternative is an interaction mode enum that can be None, Normal, WithMouse.

(Relates a bit to https://github.com/slint-ui/slint/issues/2260)