feat(backend): Phase 1 passwordless login — migration, models, toggle endpoints, unlock, delete guard, admin controls
- Migration 062: adds users.passwordless_enabled and system_config.allow_passwordless (both default false)
- User model: passwordless_enabled field after must_change_password
- SystemConfig model: allow_passwordless field after enforce_mfa_new_users
- auth.py login(): block passwordless-enabled accounts from password login path (403) with audit log
- auth.py auth_status(): change has_passkeys query to full COUNT, add passkey_count + passwordless_enabled to response
- auth.py get_current_user(): add /api/auth/passkeys/login/begin and /login/complete to lock_exempt set
- passkeys.py: add PasswordlessEnableRequest + PasswordlessDisableRequest schemas
- passkeys.py: PUT /passwordless/enable — verify password, check system config, require >= 2 passkeys, set flag
- passkeys.py: POST /passwordless/disable/begin — generate user-bound challenge for passkey auth ceremony
- passkeys.py: PUT /passwordless/disable — verify passkey auth response, clear flag, update sign count
- passkeys.py: PasskeyLoginCompleteRequest.unlock field — passkey re-auth into locked session without new session
- passkeys.py: delete guard — 409 if passwordless user attempts to drop below 2 passkeys
- schemas/admin.py: add passwordless_enabled to UserListItem + UserDetailResponse; add allow_passwordless to SystemConfigResponse + SystemConfigUpdate; add TogglePasswordlessRequest
- admin.py: PUT /users/{user_id}/passwordless — admin-only disable (enabled=False only), revokes all sessions, audit log
- admin.py: update_system_config handles allow_passwordless field
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Kyle Pope
bcfebbc9ae