inbound-upstream-result: the upstream's answer in the Inbound log

The owner, 2026-10-16: the Inbound log lacks the upstream's answer - "Не
понятна судьба письма: принято, отклонено, хост не доступен"; the result
in the row only, a page per message later if needed. Mockups 5348330 and
46b90d2, plan 295d72e.

- Migration 0012: inbound_spam_log gains queue_id, upstream_status ('',
  queued, held, sent, deferred, bounced; CHECK), upstream_relay,
  upstream_reply, upstream_at, and a partial index on queue_id. Schema 12.
- The inbound journal milter writes an accepted row with the queue id of
  end-of-message and "queued" ("held" when the filter had it held), the
  recipient as Postfix logs it (recipientAsLogged), after detaching older
  rows of a queue id Postfix uses again; no queue id, no result.
- The tailer: a delivery line no send-log row took goes to the journal -
  status, relay= ("" for none), the reply after the first status=, cut to
  255 printable bytes, the line's time; queued/held/deferred rows only,
  sent and bounced final. qmgr's expiry makes them bounced, keeping the
  last reply. cleanup's "removed (" detaches rows of a message never
  queued. Addresses in delivery lines are read by Postfix's quoting
  (loggedAddress): a quoted RCPT TO cannot end one early.
- The page: an Upstream column - a plain tag for queued and held, else a
  tag opening the host, the reply, when and what follows; "—" for refused
  mail and older rows. Help (word for word with the mockup), guide,
  architecture, security, schema-migrations, CHANGELOG.

Reviewed before the commit (technical and security, 2026-10-16); the plan
lists each finding and what it became.

Tests: store (results, finality, expiry, held, a reused id, the queue-id
index in every plan), milter (queue id, held, quoted recipient, no {i}),
logtail (relay and reply, a forged quoted recipient, Run hands the journal
what the send log did not take, cleanup's removal), view (the column, held,
null sender), e2e (both relayed messages sent with the sink's 250; an
upstream refusing connections deferred with the reason and no host, then
expired to bounced; the refused row has none). go vet + go test (26
packages) and make e2e on the test server for this tree.

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

docs/guide.md

@@ -1188,7 +1188,12 @@ anyone on the host; they hold addresses, not secrets.
 
 In the panel the lists are **Inbound › Filter lists** (global role), and what
 port 25 decided about each message is **Inbound › Log**: accepted mail with the
-filter's verdict, refused mail with the reply it was given. A row of the log
+filter's verdict, refused mail with the reply it was given. For accepted mail
+its *Upstream* column says what the upstream made of it - *queued* (not tried
+yet), *held* (in the queue by the filter's verdict, until released), *sent*,
+*deferred* (a greylisting, an upstream that cannot be reached: Postfix tries
+again) or *bounced* (refused for good, or expired in the queue; the sender
+was sent a bounce) - and opens the last reply and the host that gave it. Rows logged before 2.10.0 have no upstream result. A row of the log
 leads to the lists with its sender filled in. Beside each entry of a list is
 how often it decided a message, counted from the log - so over the days the
 log keeps - and *never* marks an entry that may have outlived its use. The