PR #5423 relaxed the email suffix whitelist: once a whitelist is
configured, non-whitelisted registrable domains are each allowed to
register one account. That behavior activated unconditionally.
Add registration_email_domain_quota_enabled (default false) to gate it:
- Off (default): restore pre-#5423 strict whitelist semantics — with a
non-empty whitelist, non-whitelisted domains are rejected with
EMAIL_SUFFIX_NOT_ALLOWED; the register/verify views restore the
client-side whitelist pre-check and allowed-domain hint.
- On: keep #5423 behavior — one account per non-whitelisted registrable
domain (EMAIL_DOMAIN_REGISTRATION_LIMIT).
- Empty whitelist keeps allowing all domains in both states.
Gating lives in validateRegistrationEmailQuota and (as a race-safety
backstop) createUserWithRegistrationEmailGuard; the repository-level
domain lock + in-tx recheck is unchanged. The admin update field is
*bool (omitted = keep current) so stale full-payload saves cannot
silently flip the switch. Email binding and OAuth auto-signup keep
their strict policy, and pending-OAuth bind-login for existing
accounts is unaffected because the handler resolves existing emails
before the quota check.
Frontend adds the toggle to admin settings (zh/en copy; whitelist hint
restored to strict wording, quota wording moved to the new toggle) and
exposes the flag via public settings + SSR injection payload.
Tests: #5423 quota tests now enable the switch explicitly; new
default-off regression tests cover register/send-code/async/pending
OAuth/OIDC create-account plus both register views; API contract JSON
and the injection drift guard are updated.
- parseSettings now reports passkey_enabled=false whenever the WebAuthn
deployment config is absent: a stale "true" row left behind after the
config is removed previously made the admin update gate reject every
settings save while the UI toggle was disabled, leaving no recovery
path from the admin panel. Added a regression test.
- update the admin settings API contract goldens with the new
passkey_enabled/passkey_configured/passkey_rp_id/passkey_rp_origins
fields.
- errcheck: check rows.Close in passkey repository (repo convention).
- staticcheck QF1001: apply De Morgan's law in WebAuthn origin scheme
validation.