Capture the v1 identity model: Microsoft Entra ID, multi-tenant app with
B2B guest invitation for partner-org employees, workforce-only
authentication in v1. Code and data are architected for dual audience
from day one (Audience enum, audience claim in sessions, audience column
+ RLS policies on shared tables, claims-based authz) so that adding Entra
External ID for customers later is a switch-flip rather than a refactor.
The dev environment uses a Microsoft 365 Developer Program tenant (free,
renewable) to unblock work while the prod tenant is being provisioned by
the org IT contact. Production requires Entra ID P1 licensing - flagged
here so it can be planned, not surprised.
decisions/README.md index updated. CLAUDE.md 'Identity' line now points
to ADR-0008.