New docs/PHASE3A_IDENTITY_AND_INSTRUCTOR_ACCESS.md covers the schema, persistent session
design, instructor accounts, the full RBAC matrix, cohort scoping (including the documented
raw-environment-id simplification), student session hardening (explicitly still
classroom/pilot identification, not production auth), CSRF, rate limiting, audit logging,
the API inventory, a security hardening checklist, test results, known limitations, the
future OIDC path, and production HTTPS/cookie expectations — with an explicit BUILT NOW vs.
FUTURE split.
Updates ENGINEERING_SOP.md (new §9/§10, closing a stale '(§9)' forward-reference that dated
back to Phase 2B), LAB_ARCHITECTURE.md status line, README.md, platform/README.md, and
platform/api/README.md (bootstrap-owner usage, new config vars, no more ADMIN_PASSWORD).