services: Add swayidle processing as service

swayidle is now also presented as a user service managed by runit on
voidlinux. It comes with the same defaults as before (300 seconds to
lockscreen, 600 seconds to screen dimming and 900 seconds before
suspending).

Additionally the lockscreen script has been updated to correctly tell a
wayland from a non-wayland session without logind being available on the
system, though it still defaults to using loginctl if it finds it.

The service runs as swayidle in the user services directory and can be
confirured using a 'conf' file which would be placed in the 'swayidle'
service directory. Timeouts can be set with `time_to_lockscreen`,
`time_to_screendim` and `time_to_suspend`.

services/sv/swayidle/log/run

@@ -0,0 +1,3 @@
+#!/usr/bin/env sh
+
+exec vlogger -t swayidle -p daemon

services/sv/swayidle/run

@@ -0,0 +1,20 @@
+#!/bin/sh
+
+time_to_lockscreen="${time_to_lockscreen:-300}"
+time_to_screendim="${time_to_screendim:-600}"
+time_to_suspend="${time_to_suspend:-900}"
+
+[ -r ./conf ] && . ./conf
+
+exec 2>&1
+
+# usual setup:
+# waylock -init-color 0x223344 -input-color 0x224444 -fail-color 0x554444 -fork-on-lock
+
+exec chpst -e "$TURNSTILE_ENV_DIR" swayidle \
+    timeout "${time_to_suspend}" "[ $(cat /sys/class/power_supply/AC/online) -eq 0 ] && sudo zzz" \
+    timeout "${time_to_screendim}" "wlopm --off '*'" \
+    resume "wlopm --on '*'" \
+    timeout "${time_to_lockscreen}" "pidof waylock || lockscreen" \
+    after-resume "wlopm --on '*'" \
+    before-sleep "pidof waylock || lockscreen"