disable client's scene node after create it (only XDGShell)

will be enabled when setting up its monitor and arrange it

Bug: https://github.com/djpohly/dwl/issues/306

call arrange() or resize() depending on c->isfloating in commitnotify

force SSD when creating an xdg_toplevel_decoration object

Closes: https://github.com/djpohly/dwl/issues/366
Not sure why GLFW apps do not get mapped when we do not tell them the
decoration method

remove selclient()

selclient() does not work well when dealing newly mapped
clients (specifically those mapped on invisible tags).

This fixes various bugs related to things not working because selclient() would
return NULL.

References: 94c8bd604870365bc201524b63158623e6f32a8f

fix unset fullscreen for all visible clients when mapping a new one

this also changes our policy about when we unset fullscreen:

dwl will unset fullscreen for clients who share tags (and monitor) with a newly
mapped client, it does not matter if the clients are visible or not

call checkidleinhibitor() in arrange() and not in focusclient()

fix checking idle inhibit state

checking `bypass_surface_visibility` first, could cause that even if the idle
inhibitor is being destroyed it will disable idle tracking

and if we couldn't get its scene tree, then assume that the surface is visible

Revert "Revert "Check that inhibitor scene tree is not null""

This reverts commit 035bb99d67b59a84cfc2e911d222fb597591a8be.

Not checking `tree != NULL` result in a segfault if the surface doesn't have a
role (for example because it is a newly created surface)

Closes: https://github.com/djpohly/dwl/issues/359

get `sel` from focustop() in focusstack()

Fixes: https://github.com/djpohly/dwl/issues/354

Revert "force line-buffered stdout if stdout is not a tty"

This reverts commit deb48ff48b186ff77a7e9d3b3ab724ff4c3c340f.

Fixes: https://github.com/djpohly/dwl/issues/253

implement ext-session-lock-v1

Revert "remove unneeded changes in commitnotify()"

This reverts commit 30c24a53ad2aaa842bc3b028ba0b98e3362dad7c.

Bug: https://github.com/djpohly/dwl/issues/349

Revert "fix flickering when resizing/spawning windows"

This reverts commit 017bb7d7521f68d37bfe656c10f45edbcc92dd61.

Bug: https://github.com/djpohly/dwl/issues/349

return early if couldn't find the popup's parent

fix popups appearing outside the monitor

and a potentially crash

improve type safety of toplevel_from_wlr_surface()

merge toplevel_from_{wlr_layer_surface,popup} into client_from_wlr_surface

now it is a big function called toplevel_from_wlr_surface

remove unneeded call to wlr_scene_rect_set_color()

wlr_scene_rect_create() requires a color as parameter

add option for set button map

fix null deref in sigchld() if Xwayland is disabled