panel-redesign: Help with seventeen topics; every box links to its own

Follows the design commit before it. Written by Sonnet, reviewed by
Opus.

  - view/help.go, templates/help.html: the mockup's topics, texts, ids
    and menu. The page shows the groups the reader's menu shows:
    Overview and Server for the global role, Outbound and Inbound by
    reach (Inbound only with the feature on), Account for everyone;
    boxes are numbered as shown.
  - Box.Help set on the boxes the mockups mark; the inbound MX box has
    its link again.
  - TestEveryHelpLinkLandsOnATopic also fails on a topic that no page
    links to, unless it is listed as menu-only (account) - and on a
    stale exception.

Known until the change that follows: the dns, dmarc and account topics
describe the three-choice report address, which the code does not have
yet; Account's DMARC box still links to #dns.

Not verified by running: three sentences rest on Postfix behaviour
(delivery is deferred when a required TLS session cannot be made; a
milter with default_action=tempfail answers 4xx; with "any recipient"
an address the upstream refuses comes back as a bounce).

Evidence
  - docs/assets/panel-redesign/evidence/help.png (1440x3600) and
    in-domain.png: headless Edge, real templates served locally with
    their fixtures - NOT from the container.
  - go test -count=1 ./internal/web/... ./cmd/panel: ok (six packages).

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

internal/web/view/outbound_queue.go

@@ -45,7 +45,8 @@ func NewOutQueue(m Meta, listing, errText string) *OutQueue {
 			Lead:   Rich("What applications handed over and the receiving server has not yet taken, as ", Code("postqueue -p"), " lists it."),
 		},
 		Queue: Box{No: "01", Title: "Waiting", ID: "out-queue", Poll: outboundQueue + "/fragment",
-			End: Plain("Refreshes on its own")},
+			Help: topicLink(HelpQueue, "What waits here and how Postfix retries"),
+			End:  Plain("Refreshes on its own")},
 		Empty:   EmptyState{Icon: "ti-stack-2", Text: Plain("Queue is empty.")},
 		Retries: Box{No: "02", Title: "How retries work"},
 	}