add support for linux-dmabuf-unstable-v1

References: https://gitlab.freedesktop.org/wlroots/wlroots/-/merge_requests/3726
References: https://gitlab.freedesktop.org/wayland/wayland-protocols/-/blob/main/unstable/linux-dmabuf/linux-dmabuf-unstable-v1.xml

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

Fixed 'unused variable' compiler warning.

Add appid field to printstatus() output

Adds an appid field to printstatus which can be used to monitor the
currently active application.

implement repeatable keybindings

allow configure x and y of outputs

add support for wp-fractional-scale-v1

References: https://gitlab.freedesktop.org/wlroots/wlroots/-/merge_requests/3511

chase wlroots!4000

References: https://gitlab.freedesktop.org/wlroots/wlroots/-/merge_requests/4000

chase wlroots!3391

References: https://gitlab.freedesktop.org/wlroots/wlroots/-/merge_requests/3991

follow upstream xwayland_surface changes

wlroots removed the `wlr_surface_is_xwayland_surface` function, and renamed `wlr_xwayland_surface_from_wlr_surface` to `wlr_xwayland_surface_try_from_wlr_surface`.

related commit: https://gitlab.freedesktop.org/wlroots/wlroots/-/commit/fbf5982e3838ee28b5345e98832f6956c402b225

use sigaction(2) for signal handling

References: http://git.suckless.org/dwm/commit/712d6639ff8e863560328131bbb92b248dc9cde7.html

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

bump version to 0.4

remove `--long` from git-describe command

return early if selmon is not part of the output layout in dirtomon()

instead of checking twice

simplify check in urgent()

we only care if it returned a client or not

arrange monitor after updating fullscreen background and lock surfaces

also update locked_bg node position in updatemons()

add blank lines to make updatemons() more readable

update comment about client_set_size() as no-op