Hub and admin-web package-lock.json were missing @emnapi/* entries that
npm 11 on the Alpha host requires, so deploy_fleet_release failed at
npm ci. Regenerate both lockfiles and retry incomplete release trees.
Add deploy_fleet_release.sh and a workflow that rolls immutable Hub
releases (including admin-web) to educraft-dev on push/PR and educraft
on main/tags, selecting silos by HUB_PUBLIC_BASE_URL middle domain.