release: 2.10.4: origin-strict - a change with neither header is refused

Cut without asking, as the owner said on 2026-10-15. A POST with neither
Sec-Fetch-Site nor Origin is refused (the commit before this); the e2e
client sends Origin. go vet, go test (26 packages) and make e2e passed on
the test server for that tree. No migration, schema 12.

CHANGELOG [2.10.4]; pins in deploy/docker-compose.yml, README and the guide
(pin, build, the sample restore message); development's "from pin" and
row 36; roadmap row. No tag.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/roadmap.md

@@ -32,7 +32,7 @@ in `git log` and [CHANGELOG.md](../CHANGELOG.md).
 | health-setup-checks | Server › Health also checks the certificate's name, Postfix's greeting and the trusted proxy (was preflight) | agreed (2026-10-13) | — | — |
 | test-email | Send a test message from the panel (was preflight) | agreed (2026-10-13) | — | — |
 | inbound-antispam-panel | Inbound antispam journal + allow/deny lists | shipped `2.1.0` | 12/12 | [plans/inbound-antispam-panel.md](plans/inbound-antispam-panel.md) |
-| origin-strict | Refuse a state-changing request that carries neither `Sec-Fetch-Site` nor `Origin` (was csrf-tokens) | done 2026-10-16, unreleased | — | — |
+| origin-strict | Refuse a state-changing request that carries neither `Sec-Fetch-Site` nor `Origin` (was csrf-tokens) | shipped `2.10.4` | — | — |
 | backup-reauth | Ask for the account password before a backup or a domain export is downloaded | shipped `2.10.3` | — | — |
 | review-2026-08-followups | Remaining findings of the 2026-08-19 code review | closed 2026-10-14 (rows placed in [audit-2026-10-12](audit-2026-10-12.md)) | — | — |
 | panel-notifications | E-mail notifications about important events | shipped `2.3.0` | 10/10 | [plans/panel-notifications.md](plans/panel-notifications.md) |