* input/layers: let new layer-surfaces take pointer focus
* input/layers: decouple pointer focus from keyboard interactivity
zwlr_layer_surface_v1::set_keyboard_interactivity:
"Layer surfaces receive pointer, touch, and tablet events normally.
If you do not want to receive them, set the input region on your
surface to an empty region."
We were previously treating keyboard interactivity also as pointer
interactivity, by forcing pointer focus onto any new
'keyboard_interactivity != none' surfaces in onMap(), as well as
redirecting all regular pointer input to any existing
'keyboard_interactivity == exclusive' surface.
* layers: rename 'interactivity' identifiers to specify *keyboard*-interactivity
The Lua config field is also renamed from 'interactivity' to
'keyboard_interactivity'.
StephanandGitHub