reboot command beside poweroff, one polkit grant; forward yukart/gnss/+; mock uses current names

--allow-poweroff becomes --allow-power. deploy/50-yukart-gw-power.pkla adds logind's
reboot actions and the deploy removes the old poweroff-only file.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DDwfd6Ki8UfG4hK6W5YpJz

deploy/50-yukart-gw-power.pkla

@@ -0,0 +1,13 @@
+# polkit (0.105, local authority): lets the svc-gw user power the host off or reboot it
+# through logind, with no sudo. svc-gw runs `systemctl poweroff` / `systemctl reboot`
+# for the display's `poweroff` and `reboot` commands (contracts BOUNDARY.md). Nothing
+# else is granted.
+# Installed to /etc/polkit-1/localauthority/50-local.d/ by scripts/deploy.sh.
+# multiple-sessions: an ssh login is another session; ignore-inhibit: no inhibitor lock
+# (none are taken on this host today) should leave the button silently doing nothing.
+[yukart-gw: power off and reboot]
+Identity=unix-user:mikkeli
+Action=org.freedesktop.login1.power-off;org.freedesktop.login1.power-off-multiple-sessions;org.freedesktop.login1.power-off-ignore-inhibit;org.freedesktop.login1.reboot;org.freedesktop.login1.reboot-multiple-sessions;org.freedesktop.login1.reboot-ignore-inhibit
+ResultAny=yes
+ResultInactive=yes
+ResultActive=yes