Replaces the v0.3.0 / v0.7.0 allowed_emails admission gate with an
admin-grant flow (roadmap item #6, SPEC §6.1 / §6.2 / §14.1 / §17).
Any valid email can sign in via OTC; a fresh user lands in
permission_state='pending' with a captured first/last/why profile,
and an admin grant flips them to 'granted' before write endpoints
accept them. Grandfathered users pass through the migration with
the column default 'granted' so existing contributors are unaffected.
The allowed_emails table stays in the schema as a fast-path bypass
pending v0.9.0's admin user-management page (item #7).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Replaces the Gitea OAuth gesture as the primary human-auth path
(roadmap item #5, SPEC §6.2). Users sign in by entering their email,
receiving a six-digit code via the existing SMTP layer, and entering
the code on a two-step /login surface. The Gitea OAuth callback
remains functional during migration — the new UI links to it as a
fallback for users with active OAuth sessions or older invite paths
— and is scheduled for removal in a future release once OTC adoption
is universal. Existing users are linked by email on first OTC sign-
in (gitea_id preserved); new users are provisioned with NULL
gitea_id and rely on email as the identity key. The migration
introduces backend/migrations/012_otc.sql (otc_codes table + users
schema rebuild for nullable gitea_id and a partial unique index on
email), two new endpoints (POST /auth/otc/request, POST /auth/otc/verify),
bcrypt as a new backend dependency for code hashing, and 11 new
tests in test_otc_vertical.py covering the happy path, expired and
consumed and wrong codes, the per-email rate limit, the allowlist
gate, the OAuth-era link path, fresh provisioning, and prior-code
invalidation on re-request. No new secrets are required — the
existing SECRET_KEY signs sessions and bcrypt's per-row salt covers
the code hashes.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>