- Add ON DELETE CASCADE to users_teams, oauth_providers, admin_permissions
and ON DELETE SET NULL (with nullable columns) to team_api_keys.created_by,
hosts.created_by, host_tokens.created_by so HardDeleteExpiredUsers no longer
fails with FK violations
- User account deletion now cascades to sole-owned teams via DeleteTeamInternal,
preventing orphaned teams with live sandboxes after account removal
- ListActiveSandboxesByTeam now includes hibernated sandboxes so their disk
snapshots are cleaned up during team deletion
- Team soft-delete now hard-deletes sandbox metric points, metric snapshots,
API keys, and channels to prevent data accumulation on deleted teams
- Extract deleteTeamCore() to deduplicate shared logic across DeleteTeam,
AdminDeleteTeam, and DeleteTeamInternal
- Fix ListAPIKeysByTeamWithCreator to use LEFT JOIN after created_by became
nullable, and update handler to read pgtype.Text.String for creator_email
