enable adaptive sync if supported

but don't cause monitors to be ignored if it fails

add support for the single pixel buffer protocol

Merge remote-tracking branch 'djpohly/main' into wlroots-next

prevent an infinite loop if try to use focusmon() with all monitors disabled

don't try to set monitor for clients in createmon()

this is done in updatemons()

set monitor for clients that don't have one in updatemons()

only if selmon is enabled and the clients are mapped

set monitor for clients that don't have one on monitor creation

don't respect size hints for fullscreen clients

Fixes: #292

change type of c->bw: int -> unsigned int

reorder isfullscreen in Client definition

initialize to zero the box used in commitnotify()

fix crash when setting a custom mode

rework outputmgrapplyortest()

first disable requested monitors, then enable and/or change mode, x and y, etc.
This is mostly what sway does

check client_from_wlr_surface() returning NULL in urgent()

fix #281

fix segfault if parent->mon is unset

use the layer surface to create popups

make sure we do not create a double fullscreen_bg

and also make sure we do not destroy it if it does not exist
Fixes: #274

conform the xdg-protocol with fullscreen translucent clients

see `setfullscreen()` for more info

always set the same monitor and tags for child clients of a client

fixes #272

do not focus clients if a layer surface is focused