Backfill the byte-identical deploy-notification callback (Gotify on every run,
Pushover on failure) that the other LXC repos already ship. Auto-discovered via
the existing ansible.cfg callbacks_enabled line, gated by NOTIFY_ENABLED env
(default off, so inert until Semaphore enables it).
Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>
