The operator-facing half of engagement Phase 1. README's stack table and
security section, plus both .env.example files, all pointed at the
removed Connect Gmail flow.
The env comments now name the three supported postures rather than one
provider — a relay as the recommendation, smtp.gmail.com:587 with an app
password as the shortest migration, an unauthenticated local MTA as the
third — and point at docs/website/UPGRADE_NOTES.md for the deployment
this actually happens to.
The OpenAPI spec is regenerated: two routes gone, three annotations
rewritten, and the dashboard's new warnings[] documented.
Co-Authored-By: Claude <noreply@anthropic.com>