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>

internal/web/view/help.go

@@ -207,11 +207,16 @@ var inboundTopics = []HelpTopic{
 	}},
 	{ID: HelpInboundLog, Title: "Inbound log", Body: []Text{
 		Rich("One row per recipient of a message offered on port 25 for an inbound domain, with what was decided: ",
-			TagOf("accept", ""), " — handed on to the upstream; ", TagOf("reject", ""), " — refused for good; ",
+			TagOf("accept", ""), " — taken for the upstream; ", TagOf("reject", ""), " — refused for good; ",
 			TagOf("tempfail", ""), " — the sender was asked to come back later; ", TagOf("quarantine", ""), " — held by the filter. ",
 			Em("Why"), " names who decided. ", Code("rspamd"), " is the spam filter, with its action, the score against the reject threshold and the heaviest symbols; ",
 			Code("postfix"), " is the relay's own rule — an unknown recipient, a sender domain that does not exist — with its reply; ",
-			Code("selfpost"), " means nobody judged the message: it was relayed with no filter attached. Accept says what this server did, not what the upstream did with the message afterwards.",
+			Code("selfpost"), " means nobody judged the message: it was relayed with no filter attached. ",
+			Em("Upstream"), " says what became of an accepted message: ", TagOf("queued", ""), " — not tried yet; ",
+			TagOf("held", ""), " — held in the queue by the filter, not tried until it is released; ",
+			TagOf("sent", ""), " — the upstream took it; ", TagOf("deferred", ""),
+			" — the upstream put it off or could not be reached, and Postfix tries again; ", TagOf("bounced", ""),
+			" — the upstream refused it, or it waited in the queue too long, and the sender was sent a bounce, if it had a return address. It opens the last reply and the host that gave it. A refused message has no upstream result, and neither has a row logged before 2.10.0.",
 			Br(), Br(),
 			"Accepted mail is recorded as it passes; refused mail is read from ", Code("mail.log"),
 			", so its row has no subject, and a message refused after its text was sent is one row however many recipients it had. A refusal to relay for a domain that is not an inbound one is every scanner on the internet and is not recorded. Rows are kept for the number of days set in Settings, and never more than 10 000."),