check null in toplevel_from_popup

managed to SEGFAULT the server by trying to create a popup
without setting a parent first.

Not sure if this is dwl or wlroots issue, so also opened a ticket upstream: https://gitlab.freedesktop.org/wlroots/wlroots/-/merge_requests/3811

layersurface: create a dedicated scene tree for popups

this tree should be always above the top layer

Fixes: https://github.com/djpohly/dwl/issues/328

client: don't change border color during drags

Fixes: https://github.com/djpohly/dwl/issues/318

fix crash in dirtomon() when selmon is disabled

closemon() now updates selmon if needed

use just one loop in outputmgrapplyortest()

we do the magic in updatemons()

move focus and clients off disabled monitors

only raise the client's node in monocle()

Fixes: https://github.com/djpohly/dwl/issues/326

sort util.c functions

limit the line length to 79 in the readme

mention the polkit dependency when using elogind or systemd-logind

Bug: https://github.com/djpohly/dwl/issues/138

Revert "stop trying resize clients during commitnotify()"

This reverts commit 2d9d758c8dec083178ff78b154da784b97260bd1.

wasn't meant to be pushed to main

update comment about exclusive focus in focusclient()

stop trying resize clients during commitnotify()

instead resize them in configurex11()

allow unmanaged clients (like dzen or dmenu) to have keyboard focus

delete the idle protocol xml file

disable and destroy monitor's layer surfaces when it's being destroyed

Fixes: https://github.com/djpohly/dwl/issues/314

use `/* */` for comments in applybounds()

fix bad indentation in createpointer()

rename dragicondestroy() -> destroydragicon()

to match the rest of the code