Persist Bluetooth power state across reboots (#5683)

* Persist Bluetooth power state across reboots

BlueZ defaults to AutoEnable=true, which forces controllers on at boot
regardless of the last user-set state. Setting AutoEnable=false makes
bluetoothd respect the persisted Powered state, so toggling off in
bluetui (or any DBus client) survives a reboot.

Adds the change to the install path and a migration for existing setups.

* Set reboot-required in Bluetooth persistence migration

Per review feedback, the AutoEnable=false change only takes effect on
bluetoothd startup. Without setting reboot-required, omarchy-update-restart
won't prompt the user to reboot, so the fix would only kick in at their
next organic reboot — by which time the bug may appear unfixed.

Matches the convention in migrations/1776346552.sh and similar.

* No need to ask for a reboot when this is available on the next one

---------

Co-authored-by: David Heinemeier Hansson <david@hey.com>

migrations/1778291336.sh

@@ -0,0 +1,3 @@
+echo "Persist Bluetooth power state across reboots"
+
+sudo sed -i 's/^#\?AutoEnable=.*/AutoEnable=false/' /etc/bluetooth/main.conf