base-trixie: the image on Debian trixie, Postfix 3.10.13; Received: hidden on 465/587

The runtime base is debian:trixie-slim, the build stage golang:1.26-trixie:
Postfix 3.10.13 with upstream's 2026 security fixes up to the August
batch, libmilter 8.18.1, OpenSSL 3.5. Every citation of another program in
code, scripts and documents was re-read against the trixie sources
(dev/upstream; bookworm's kept in dev/upstream-bookworm) and updated;
development.md's cited-package table holds the trixie versions.

What the re-reading changed in behaviour:
- logtail: reject lines with sasl_method/sasl_username/sasl_sender
  (smtpd_check.c:1019-1026); cleanup's "removed (canceled)" forgets a
  port-25 id (cleanup_api.c:363-364).
- internal/postfix/retry.go reads postconf's stdout only: since 3.9 a
  deprecated-parameter warning on stderr made one value too many and the
  panel fell back to the compiled-in retry policy.
- logrotate-loop.sh: logrotate 3.22 exits 1 when it ignores a config;
  the loop refuses on that output whatever the status.
- postfix-config.sh: cyrus_sasl_config_path set explicitly (bookworm's
  07_sasl_config.diff is gone); maillog_file_permissions=0640; mynetworks
  explicit; Dockerfile: SYNC_CHROOT= in /etc/default/postfix,
  opendkim-tools dropped, openssl named, systemd-standalone-sysusers so
  cron does not bring the whole of systemd.
- The selfpost group is 10998, outside the system range 100-999: in
  trixie a package took 998 and the build failed (owner's decision:
  a conflict-free id, the distribution's own ids untouched). The
  entrypoint hands /data back by name when the user or the group differs.
  Guide, backup refusal text, help (design commit 68ec8b2), e2e.
- smtpd_hide_client_session=yes on smtps and submission (owner's
  decision): Received: names no client, TLS, login or protocol; port 25
  keeps the full header. e2e checks both.
- test/upstream/opendkim-probe.sh makes keys with openssl genrsa.

Tests: on the server, make e2e exit 0 (674 s, the image built on trixie),
go vet + go test 27 packages ok. CHANGELOG [Unreleased], guide,
architecture.md, security.md, roadmap.

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

internal/postfix/queue_test.go

@@ -12,7 +12,7 @@ import (
 
 // TestFakePostqueue is not a test: it is the fake `postqueue -p` the tests
 // below run in place of the real one, writing SP_FAKE_POSTQUEUE_BYTES bytes of
-// queue entries composed by hand after the layout of Postfix 3.7.11's
+// queue entries composed by hand after the layout of Postfix 3.10.13's
 // src/postqueue/showq_compat.c.
 func TestFakePostqueue(t *testing.T) {
 	if os.Getenv("SP_FAKE_POSTQUEUE") != "1" {
@@ -76,7 +76,7 @@ func TestQueueIDsReadsAListingUnderTheCap(t *testing.T) {
 // The reconcile sweep decides whether a message is still Postfix's problem, so
 // the parser must pick queue ids out of a listing and nothing else out of it:
 // not the header, not the byte-count trailer, and above all not a deferred
-// entry's reason line. The listing is composed by hand. Postfix 3.7.11
+// entry's reason line. The listing is composed by hand. Postfix 3.10.13
 // (src/postqueue/showq_compat.c, showq_message()) right-aligns a reason to
 // column 76, so it reaches the left margin only when it is 76 characters or
 // longer; the one here is put at the margin as the hard case.