design: Help covers every section; boxes link to their topic

The owner's decision (2026-10-10): help is needed by almost every
section, not by Overview and Outbound alone. The Help mockup had six
topics while other screens already linked to topics it did not have
(#dmarc, #inbound).

  - src/help.html: seventeen topics in five boxes - Overview (checks,
    certificate, rdns), Outbound (dns, apps, limits, log, queue, dmarc),
    Inbound (inbound, upstream, recipients, filter), Server (backup,
    users, settings), Account (account) - one paragraph each, and the
    side menu lists them by group.
  - A box head gets the sp-help link where a topic now exists: health,
    out-domain-settings, out-app, out-log, out-message, out-queue, the
    three DMARC screens, in-domains, in-domain, backup, users, user,
    settings. No link on boxes that explain themselves (confirmations,
    the shown-once password, sign-in) and at most one per box.
  - outlines.json regenerated (check.py --write): only help changed -
    Outbound holds six topics, and Inbound, Server and Account are new
    boxes. 0 violations.

The dns, dmarc and account topics describe the report-address scheme the
owner decided the same day (no reports / the SelfPost address / a typed
address, no user default); the account and out-domain-settings mockups
are redrawn for it in the change that follows.

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

docs/assets/panel-redesign/panel/outlines.json

@@ -123,7 +123,10 @@
     {
      "is-9": [
       "box[Overview]:help×3",
-      "box[Outbound]:help×3"
+      "box[Outbound]:help×6",
+      "box[Inbound]:help×4",
+      "box[Server]:help×3",
+      "box[Account]:help"
      ]
     }
    ]