docs: clear shipped plans and closed work out of the documents

Owner, 2026-10-18: "Надо почистить документы от устаревшего и сделанного."

- Deleted, shipped: plans/delivery-log-storage, from-header-binding,
  inbound-antispam-panel, inbound-upstream-result, panel-dkim-signing,
  panel-notifications, and the own-mta-builds analysis (its three rows
  shipped as 2.6.1, 2.7.0, 2.8.0). What outlived them moved first: when a
  filter-list counter is worth a migration, and the notifications' "when"
  table, into architecture.md; the sender check's own-process trigger into
  security.md. Code comments that cited them point at architecture.md or
  security.md; CHANGELOG keeps their names, unlinked.
- Kept, marked closed: audit-2026-10-12, assumptions-2026-10-14 and
  security-audit-2026-10-17 - the code cites their finding ids in 50-84
  files. Their file:line refs are of the tree each audited.
- roadmap.md: open work only - stage H of the security audit (the owner's),
  go-milter-upstream (the owner posts), and queue-table, which the
  redesign left undecided and only its own shipped section still named;
  Dropped and Ideas as they were. 2.x versioning instead of 1.x.
- development.md: the 47-row planned-version-cuts table (history, in the
  CHANGELOG) gone; a stage's last step now removes its roadmap item and
  plan. Docs map lists the closed audits.
- panel-redesign.md: the done checklist out; Room for roadmap items says
  which drawn screens are unbuilt and why.
- Stale facts fixed: schema-migrations.md and architecture.md at schema 14
  (0013's users columns and user_links, 0014's secure TLS mode);
  security.md's accepted risk "profile saved without the password" - the
  e-mail asks for it since 2.14.0.

Tests: go build, go vet; go test of cmd and the touched internal packages
pass except logtail's three Windows-bound rotation tests (rename of an open
file; CI is Linux). Only comments changed in Go.

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

test/e2e/mail_helpers.go

@@ -88,8 +88,9 @@ func verifyDKIM(raw []byte, domain string) error {
 	return nil
 }
 
-// checkPanelSignature is the oracle of docs/plans/panel-dkim-signing.md: the
-// message carries one DKIM signature, the panel's, for domain - signed as
+// checkPanelSignature is the oracle of the panel's DKIM signer
+// (docs/architecture.md § DKIM signing): the message carries one DKIM
+// signature, the panel's, for domain - signed as
 // OpenDKIM signed until 2.8.0 (relaxed/simple, rsa-sha256, From over-signed)
 // - and dkimpy (python3-dkim in the sink image), an implementation that is
 // not go-msgauth, the panel's library, verifies it. Stage 1 compared it with

test/e2e/port25_config_check.go

@@ -54,7 +54,7 @@ var port25Cases = []port25Case{
 			// The SMTP-smuggling defence. Postfix 3.10.13 has it by default
 			// (src/global/mail_params.h, DEF_SMTPD_FORBID_BARE_LF "normalize");
 			// set explicitly since 2.6.1, when the image ran Postfix 3.7.11,
-			// whose default was "no" (own-mta-builds, § 5), and kept so the
+			// whose default was "no" (docs/security.md § Mail path), and kept so the
 			// listener does not depend on the default. testInboundBareNewline
 			// drives it.
 			{param: "smtpd_forbid_bare_newline", contains: "normalize", wantExact: true},

test/e2e/sink/Dockerfile

@@ -4,7 +4,7 @@
 # the panel's signer added) straight off disk. smtp-sink ships in the postfix
 # package itself. python3-dkim (dkimpy 1.1.8-2 in trixie, /usr/bin/dkimverify)
 # is the independent DKIM verifier the suite holds the panel's signer to
-# (docs/plans/panel-dkim-signing.md); it looks the keys up through the
+# (docs/architecture.md § DKIM signing); it looks the keys up through the
 # stand's CoreDNS (compose.override.yml, sink's dns).
 FROM debian:trixie-slim