audit 2c: the rest the sources contradict, and the documents

Code and config:
- C-M7: a DMARC report's explicit <pct>0</pct> stays 0; only an absent
  pct takes RFC 7489 § 6.3's default 100 (Pct *int).
- C-D1: docs/development.md now tables the Debian versions the citations
  were read at (postfix 3.7.11-0+deb12u1, opendkim and libopendkim11
  2.11.0~beta2-8+deb12u1, libmilter1.0.1 8.17.1.9-2+deb12u2, libsasl2-2 and
  sasl2-bin 2.1.28+dfsg-10, supervisor 4.2.5-1, logrotate 3.21.0-1 - read off
  the image with dpkg-query, 2026-10-15); the e2e stand's new
  checkCitedPackageVersions fails when the image it built differs.
- C-E2: the e2e zone's SOA serial only grows (CoreDNS v1.14.6's file
  plugin reloads on a grown serial, not on mtime); Corefile comment says
  so; TestZoneSerialGrows.
- C-K8, C-K9: the e2e compose and stage comments say how
  --project-directory and .env resolve.
- D-arch:154: postfix-config.sh's "Postfix insists" comment says what
  TLS_README advises and that smtpd reads the key as root.
- B-G7: inflight.go's reservationTTL comment: a dropped client does give
  ABORT (smtpd_proto() -> mail_reset() -> milter_abort()); the TTL is for
  smtpd dying or the milter connection breaking.
- D-guide:301: the nginx fragment's first-certificate command now reaches
  certbot (--entrypoint certbot, --standalone, port 80 free), and the
  renewal loop passes --webroot -w /var/www/certbot - a standalone
  certificate would otherwise renew standalone while nginx holds port 80
  (certbot docs, "Renewing certificates": the issuing plugin is used
  "unless you specify other plugins or options", and options of a
  successful renewal are saved). The register's proposal missed that.

Documents: every D-arch, D-guide and D-sec claim the register's Answers E
found false or partly true, rewritten - by three Sonnet agents, one per
document, then reviewed: two proposals were obsolete after this stage's
fixes and not used (a bounce's From: line - extract_from = "smtp" now;
"Origin: null" - Referrer-Policy is same-origin now); a stand
observation the agent had dated from a commit is now tied to the e2e test
that checks it; the SQLite writers paragraph describes _txlock=immediate;
the log tailer's rotation paragraph describes the minute's grace; the
guide's nginx steps were put in working order (links and modes before
`up`, no reconfigure step). "Deferred" is kept for Postfix's queue in the
guide too. guide.md's CRLF from the agent normalised.

Stand (2026-10-15, make e2e, exit 0, the version gate and zone serial
test included); go vet and go test ./... pass on the server (24 packages).

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

test/e2e/process_check.go

@@ -2,6 +2,9 @@ package e2e
 
 import (
 	"fmt"
+	"os"
+	"path/filepath"
+	"regexp"
 	"strings"
 	"time"
 )
@@ -83,3 +86,46 @@ func checkInboundRelayOff(s *stack) error {
 	}
 	return nil
 }
+
+// checkCitedPackageVersions compares the Debian packages the image runs with
+// the versions their sources were read at (docs/development.md, the table
+// between the cited-package-versions markers). The image installs unpinned
+// from a moving bookworm, so a point release changes them on a rebuild
+// without anyone reading what changed (assumptions C-D1).
+func checkCitedPackageVersions(s *stack) error {
+	doc, err := os.ReadFile(filepath.Join(s.repoRoot, "docs", "development.md"))
+	if err != nil {
+		return err
+	}
+	text := string(doc)
+	start := strings.Index(text, "<!-- cited-package-versions -->")
+	end := strings.Index(text, "<!-- /cited-package-versions -->")
+	if start < 0 || end < start {
+		return fmt.Errorf("docs/development.md has no cited-package-versions table")
+	}
+	row := regexp.MustCompile("(?m)^[|] `([^`]+)` [|] `([^`]+)` [|]$")
+	want := map[string]string{}
+	var names []string
+	for _, m := range row.FindAllStringSubmatch(text[start:end], -1) {
+		want[m[1]] = m[2]
+		names = append(names, m[1])
+	}
+	if len(names) == 0 {
+		return fmt.Errorf("the cited-package-versions table lists no package")
+	}
+	out, err := s.execIn("selfpost", append([]string{"dpkg-query", "-W", "-f", "${Package} ${Version}\n"}, names...)...)
+	if err != nil {
+		return fmt.Errorf("dpkg-query: %v\n%s", err, out)
+	}
+	var diffs []string
+	for _, line := range strings.Split(strings.TrimSpace(out), "\n") {
+		f := strings.Fields(line)
+		if len(f) == 2 && want[f[0]] != f[1] {
+			diffs = append(diffs, fmt.Sprintf("%s: the image has %s, the citations were read at %s", f[0], f[1], want[f[0]]))
+		}
+	}
+	if len(diffs) > 0 {
+		return fmt.Errorf("packages changed under the citations - re-read them (docs/development.md):\n%s", strings.Join(diffs, "\n"))
+	}
+	return nil
+}