Adds instance_role + reserved email/mfa_secret columns to admin_users, creates app_members for per-app role grants, and creates api_keys for bearer-token credentials. Schema snapshot re-blessed. Reserves invites and service_accounts shapes in a trailing comment block — both land in their own migrations when those flows ship. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>