- migrations/017: email, login_identifier, password_hash, last_login_at, credential_token_*
on students. Fully additive, both nullable/independent, no destructive change.
- students-auth.js: shared credential/token lifecycle (issue/consume/find), reusing
instructors' exact scrypt password.js verbatim.
- student-auth-routes.js: /api/student/login, /activate, /change-password,
/request-password-reset (anti-enumeration, dev-only token echo), /reset-password, /profile.
- metrics.js: hand-rolled /metrics Prometheus exporter, login success/failure counters, no
student/instructor ID ever used as a label value.
- migrations/018: classroom_sessions/participants/events/announcements/help_requests, with a
partial unique index enforcing at most one live classroom per cohort at the DB level.
