DRAFT: systemd/postmarketos-base-systemd: add trigger to run preset-all

This adds a trigger to postmarketos-base-systemd that runs
`systemctl preset-all` any time unit files are changed on the system.
This means we can drop the systemd macro for pkg pre-install/de-install
scripts, and avoid making abuild complicated for handling systemd stuff.

The downside with this approach is that users who want to permanently
disable can no longer do `systemctl disable <unit>`, and instead have
to do `systemctl mask <unit>`. Given how much this improves other stuff,
especially wrt upstreaming the abuild split func stuff, I think this
is a worthwhile trade-off. We can always improve on this more in the
future, since this trigger thing would be easy to roll back/replace.

fixes #3494

Also see: #3476
Also see: #2804

extra-repos/systemd/postmarketos-base-systemd/APKBUILD

@@ -2,13 +2,14 @@
 # Co-maintainer: Clayton Craft <clayton@craftyguy.net>
 # pmbootstrap installs this, if systemd is selected in "pmbootstrap init".
 pkgname=postmarketos-base-systemd
-pkgver=27
-pkgrel=0
+pkgver=28
+pkgrel=1
 pkgdesc="Meta package for running postmarketOS with systemd"
 url="https://postmarketos.org"
 arch="noarch"
 license="GPL-3.0-or-later"
 options="!check"
+triggers="$pkgname.trigger=/usr/lib/systemd/*"
 
 # systemd <-> util-linux is an expected cycial dependency
 # Also we can't parse .note.dlopen yet.

extra-repos/systemd/postmarketos-base-systemd/postmarketos-base-systemd.trigger

+#!/bin/sh
+
+# system units
+systemctl preset-all
+
+# session/user units
+systemctl --global preset-all
+
+cat <<EOF
+---------------------------------------------------------------------------------------------------------
+HINT: To permanently DISABLE a systemd unit, use: systemctl mask <unit>
+HINT: To permanently ENABLE a systemd unit, add a preset for it in the appropriate /etc/systemd/*-preset
+---------------------------------------------------------------------------------------------------------
+EOF