- TMDO_Native_Restorer::run() takes an optional group; the CLI gains
`bridge-restore-native <entity> --group=<g>`.
- New retire(): once native meta holds every non-NULL value of a group's
flat table (checked against the persisted field definitions), forget
its registry_meta row and rename the table to <table>_retired_<Ymd>, so
orphan restore no longer routes its keys to the flat table. Refused
while a plugin still registers the group or any value differs.
CLI: `--group=<g> --retire`.
- For retiring the user `sso` group (SSO AddOn deprecation).
- Verify: core unit 659 / integration 479 green, phpcs clean
- PR: PR-042
