Treat TOTP and Passkey as alternative enrolled factors across login and
sensitive account operations. Gate every primary login transport before
issuing a session, require WebAuthn user verification, and consume login
challenges atomically with session creation.
Reuse the shared verification UI for login, 2FA management, and account
deletion. Require scoped, single-use deletion proof; recheck the session
inside the deletion transaction and revoke all sessions afterward.
Validation: controller/service/model/middleware tests; real SQLite 3.50.4,
MySQL 8.4.11, and PostgreSQL 16.15 security regressions; frontend tests,
TypeScript, targeted lint, formatting, and production build.
Deploy the frontend and all backend nodes together. No schema changes.
