hive-c0re now auto-creates the Forgejo push webhook for
internal/knowledge at startup (ensure_webhook). this is what was
missing — the webhook endpoint existed but was never registered in
forgejo, so merging iris's PR didn't trigger a pull.
also adds a periodic hourly pull as a fallback (and an immediate pull
at startup to reconcile commits that landed while c0re was offline).
fixes#1244.