Restore Project

Walk back a purge. A purged project is recoverable for 30 days: its row and its contents are kept, hidden from every list and read, and permanently deleted only once the window expires. **What comes back:** the project and exactly the resources the purge removed. A resource you had deleted yourself before the purge stays deleted. **What does NOT come back, on purpose:** every credential the purge revoked stays revoked, and every grant it cleared stays cleared. API keys and service accounts pinned to the project are not re-issued, vault credentials and webhook endpoints scoped to it are not undeleted, and member grants and pending-invite scopes are not restored. Bringing a credential or a grant back would re-grant access somebody deliberately ended, so the restore reports them under `still_revoked` instead. Re-create the credentials and re-grant the members the project still needs. The project returns ARCHIVED, the state it was purged from, so nothing dispatches or bills inside it until you unarchive it. Refused with `409 project_not_purged` when the project was never purged, `409 project_restore_window_expired` once the 30 days have passed, and `409 project_name_taken` when another project has taken this one's name since the purge (a purge frees the name immediately - rename the project holding it, then restore).