audit 4: cards ordered by number, a notification owed to each recipient

The cards layout (owner, 2026-10-13; the mockup first, b90a2f0): box_open
writes data-order for a box with InCards and a number, and panel.css orders
by it up to twelve - Health's eight and the kit's three.
TestCardsBoxesCarryTheirNumberAsTheirOrder reads the rendered pages.

Notifications (owner, 2026-10-14): migration 0011, notify_addressees. open
sends a subject's first message to every recipient and records who was
handed it; followUp, on every check while the subject is open and still
wrong, hands it to the owed and untold who are still recipients; closed
sends the end to the told (all recipients for a subject from before the
table). Tests: a failed copy goes out at the next check, once; the hourly
ceiling holds one back; a user added mid-subject hears nothing of it.

Also in the roadmap, from the owner today: dns-record-collapse,
notification-mail-recheck, settings-save-row (agreed, design first).

Tested on the test server: go vet + go test of 25 packages, make e2e (all
pass, 644 s) on this tree.

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

docs/plans/panel-notifications.md

@@ -115,5 +115,5 @@ to the owner before any code ([panel-redesign.md](panel-redesign.md)
 - [x] Panel: Account, Settings, Health card, help
 - [x] guide.md, architecture.md, security.md, schema-migrations.md
 - [x] `go vet`, `go test`, e2e: a level-2 refusal reaches a mailbox as a signed notification (on the test server: vet ok, 23 packages ok, e2e ok; "once" and "clears" are held by the unit tests of `internal/notify`)
-- [x] Technical review — **Opus** (2026-10-12; no Critical. Fixed: refusals counted by the registered domain and only under a limit, with an index of their own; account e-mails may be at public mail hosts; "said" means sent; DNS checks must be 45 minutes apart; the notifier's own mail is not a queue subject and a cut or unreadable listing is no listing; the tables must name the selector the panel shows; an unanswered `a`/`mx` lookup is not an SPF mismatch; a pass stops between domains at shutdown; days are rounded as a person counts. Left as found: a recipient whose copy failed while another's went out is not retried; a certificate that lives under 14 days is reported at each renewal)
+- [x] Technical review — **Opus** (2026-10-12; no Critical. Fixed: refusals counted by the registered domain and only under a limit, with an index of their own; account e-mails may be at public mail hosts; "said" means sent; DNS checks must be 45 minutes apart; the notifier's own mail is not a queue subject and a cut or unreadable listing is no listing; the tables must name the selector the panel shows; an unanswered `a`/`mx` lookup is not an SPF mismatch; a pass stops between domains at shutdown; days are rounded as a person counts. Left as found: a recipient whose copy failed while another's went out is not retried (since 2.5.4 it is: audit 2026-10-12, stage 4); a certificate that lives under 14 days is reported at each renewal)
 - [x] Security review — **Fable** (2026-10-12; no Critical. Fixed: the limit notification was built on the domain a client writes in `MAIL FROM` - a mail cannon and a way to write to another tenant's users; a ceiling of 60 messages an hour; [security.md](../security.md) corrected on who can submit locally and on what the account e-mail now is. Recorded as accepted, with a roadmap candidate: an application can have a message signed as the server by writing its name into `From:` - the header is not held against the login, for sending domains either)