send log: rows belong to a domain by id (audit L12, 0008)

A domain user's log, the message page, a domain's statistics, the level-2
count and the notifier's refusal count picked send-log rows by domain name,
so a domain deleted and re-added under its old name showed its earlier mail
to the next assignee and went on counting it.

Migration 0008 (not run on the live database yet, so extended here):
send_log.domain_id and inbound_spam_log.inbound_domain_id, REFERENCES ...
ON DELETE SET NULL, filled once by name from the registry as it is at
migration time, each with an (id, created_at) index.

- Writes: InsertQueued / InsertRejected set domain_id to the domain of the
  row's login (loginDomainID) - the journal milter and the sender check's
  refusal rows both go through them; the inbound journal sets
  inbound_domain_id from the inbound domain's name at insert.
- Reads: SendLogFilter.DomainIDs (was Domains, by name) and
  InboundSpamFilter.DomainIDs are the scope; the global role still reads
  everything. The message page checks row.DomainID against the user's
  domains. DomainSendStats and CountMessages keep their name argument and
  select domain_id = (SELECT id FROM domains WHERE name = ?). The notifier
  joins send_log.domain_id to the domain and its application.
- DMARC reports stay by name on purpose (a report is about the DNS name).

Tests: store - scope by ids; a re-added domain's log, level-2 count and
statistics hold its own row only, the global log both; inbound scope by
ids. Handlers - the new assignee gets 404 for the old row's page and does
not see it in the log, the global role sees both. Tests that wrote rows for
a login that is no application now register it (a row is a domain's through
its application). Schema at 0008 with the two columns and indexes.

schema-migrations row 8, CHANGELOG [Unreleased], audit plan line ticked,
roadmap 19/62.
Evidence: go vet ./... clean; go test ./... ok locally but for the two
Windows-only tests; the server run follows before the push.

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

docs/audit-2026-10-12.md

@@ -672,7 +672,7 @@ has already run is never edited — the next file is added; the published
 - [x] **Import validates like the form**: route `DMARCRua`, IPs, limit mode,
    window and count through the same parsers; refuse the file with the
    validator's text. Tests per field. — **Opus**
-- [ ] **Send-log rows belong to a domain by id** (L12; owner, 2026-10-12).
+- [x] **Send-log rows belong to a domain by id** (L12; owner, 2026-10-12).
    `send_log.domain_id INTEGER REFERENCES domains(id) ON DELETE SET NULL` in
    migration `0008`, backfilled once by name against the registry as it is at
    migration time (rows of a domain already gone stay NULL); written by the
@@ -686,6 +686,8 @@ has already run is never edited — the next file is added; the published
    migration — my proposal, so that the two logs do not follow two rules.
    Tests: delete-and-re-add shows nothing to the new assignee; the old rows
    are still in the global log. — **Opus**
+   *Done 2026-10-14.* DMARC reports stay by name on purpose: a report is
+   about the name in DNS, and whoever holds the name now is its reader.
 - [ ] Docs: security.md § Roles (the guard) and the struck accepted risk, guide
    § Domain export, schema-migrations.md. — **Sonnet**
 - [ ] **Which key OpenDKIM signs with, seen and not reasoned** (owner,