Use `all-scroll` instead of `fleur` xcursor shape for window dragging

When there are no xcursor themes available, Wayland uses its own built-in shapes [1].
Wayland (and thus to extend wlroots) is based on the XDG's cursor spec [2],
which itself is based on CSS' [3][4], neither of which define `fleur` shape. So dwl,
without any external themes, falls back to `default` shape when dragging a window.
There is `all-scroll` shape that is being symlinked to (or vice versa) by `move`,
`dnd-move`, `grabbed` and `fleur` shapes by various themes.

Since `all-scroll` is being symlinked to anyway, and has been part of all relevant
specs as the shape for this use case for a very long time now, use it instead.

[1] https://gitlab.freedesktop.org/wayland/wayland/-/blob/main/cursor/cursor-data.h#L559
[2] https://www.freedesktop.org/wiki/Specifications/cursor-spec
[3] https://drafts.csswg.org/css-ui/#cursor
[4] https://developer.mozilla.org/en-US/docs/Web/CSS/cursor

Fix crash disabling monitor with locked surface

Cleanup comments

fix: shouldn't configure uninitialized layer_surface

fix: crash when open some x11 app

allocate with LISTEN_STATIC

Fixes: https://codeberg.org/dwl/dwl/issues/723
Supersedes: https://codeberg.org/dwl/dwl/pulls/724

rename some listeners

To keep consistency with the rest of listeners

destroy keyboard group after unlinking listeners

Last commit addressing the issue mentioned in
0925fe956aeddb983875f0fd892e9049e2d8cb76

unlink global listeners on destroy

Continuation of 0925fe956aeddb983875f0fd892e9049e2d8cb76

Partially revert "Line saver: LISTEN_STATIC macro"

This reverts commit 33bcd2e4ca892bb0b558660c99ed63a3dfdd9011.

We keep LISTEN_STATIC for three instances where we use it. We use
simple listeners for the rest of signals.

This is the continuation of 0925fe956aeddb983875f0fd892e9049e2d8cb76

unlink some destroy listeners

Recently wlroots was updated to assert that signals do not have listeners
attached on destroy.

This is just a preliminar work to fix dwl. At the moment dwl will trigger the
assertions at exit.

References: https://gitlab.freedesktop.org/wlroots/wlroots/-/merge_requests/4918

do not call waitid(2) in the signal handler when Xwayland is enabled

waitid(2) is not a async-signal-safe function acording to signal-safety(7)

We can stop doing this because wlroots!4926 allows compositors to install
signal handlers for SIGCHLD.

References: https://gitlab.freedesktop.org/wlroots/wlroots/-/merge_requests/4926

use wlr_xwayland_surface_has_window_type() (wlroots!4553)

References: https://gitlab.freedesktop.org/wlroots/wlroots/-/merge_requests/4553

manually call updatemons in powermgrsetmode()

Fixes: https://codeberg.org/dwl/dwl/issues/713

specify version for presentation-time (wlroots!4858)

References: https://gitlab.freedesktop.org/wlroots/wlroots/-/merge_requests/4858

check if the backend supports explicit sync before creating the object (wlroots!4848)

References: https://gitlab.freedesktop.org/wlroots/wlroots/-/merge_requests/4848

fix a use after free

This line makes dwl crash after closing mpv with the switchtotag patch.

remove unused link member from KeyboardGroup

unnecessary since grouping Keyboard wl_list to use wlr_keyboard_group in 023efce

ΔSLOC: -1

disable scene node unless it is unmanaged

send a configure to unmanaged clients when mapping