release: 1.3.0: 1.3.0-1.3.1: security pass, queue persist, full backup layout

[1.3.0]
Security and quality after 1.2.5: domain-admin send-log authorization, fail-closed sign-in and application delete, level-2 rate-limit race fix, restore Resync, expanded tests, operator docs, release CI, and OFL for IBM Plex. Upgrading from 1.2.x is a tag bump; no migration.
Added:
  - licence: the SIL Open Font License 1.1 text now travels with the IBM Plex
  - docs: agreed roadmap item **queue-retries** — show this Postfix's retry
Security:
  - The independent security review of the send-log authorization and
Fixed:
  - test (e2e): send-log status scrapers follow the badge markup in
  - security (panel): the Deliveries list is scoped to a domain administrator's
  - mail (level-2 rate limit): the ceiling is no longer overshot by messages that
  - panel (sign-in): a session that cannot be written to the database no longer
  - panel (applications): deleting an application removes its SASL credentials
  … (2 more in CHANGELOG)
Changed:
  - docs: operator and as-built docs aligned with the code after a full
  - docs: [guide.md](docs/guide.md) reorganised into **Installation**, **Instance
  - docs: the 2026-08-13 full-tree review plan is complete — every phase (P0–P7)
  - licence: [NOTICE](NOTICE) tells modifiers to update `SourceURL` in
  - ci: the release image is published only for a **published** GitHub Release
  … (9 more in CHANGELOG)
[1.3.1]
Retry policy in the panel, persistent Postfix queue, and self-contained full backups. Mail queue and delivery history show this Postfix's first retry, backoff cap, and queue lifetime. Deferred mail survives container recreate. Full backups now archive `data/`, compose, `.env`, and `certs/`; the archive layout breaks 1.3.0 flat backups (unpack those with `tar xzf backup.tar.gz -C ./data` as before). Upgrading from 1.3.0 is a tag bump; no schema migration.
Added:
  - Mail queue and a delivery's history show this Postfix's retry policy
  - docs: **Plan checklists** in [development.md](docs/development.md) — format,
  - docs: **Implementation checklists** with model routing in
  - docs: roadmap candidates **send-log-retention** (panel Settings for delivery
  - Postfix queue under `/data/postfix/queue` — deferred and active mail survive
  … (1 more in CHANGELOG)
Changed:
  - **Breaking:** full-backup archive layout — paths are prefixed with `data/`;
  - docs: operator guide, architecture, security, and backup UI updated for
  - docs: HTML mockups for a full panel UI refresh
Changed:
  - docs: panel UI mockups after review — Status restored to live readings
  - docs: panel UI design system and mockups rebuilt as separate pages
  - docs: panel UI mockups — add-domain sits in the list card (Domains and
Fixed:
  - ci (GHCR): per-arch package tags (`X.Y.Z-amd64`, `X.Y.Z-arm64`) are dropped

Squashed CHANGELOG sections: [1.3.0], [1.3.1].

Full detail: CHANGELOG.md (1.3.0, 1.3.1).

docs/plans/inbound-relay.md

@@ -3,9 +3,10 @@
 **Status:** agreed  
 **Version:** target bump **1.x** MINOR; **`2.x` possible** — to be settled once
 the implementation lands (do not fix a major in advance).  
-**Order:** recommended next among agreed 1.x+ items (after `internal/web` split
-and the domain-admin role, both shipped — see [CHANGELOG](../CHANGELOG.md)
-`[1.2.0]`).
+**Order:** queue-retries shipped in `[1.3.1]`; this is next as the largest
+remaining 1.x+ **feature**. The 2026-08-13 full-tree review follow-ups closed
+in `[1.3.0]`. The domain-admin role and `internal/web` split have shipped —
+see [CHANGELOG](../../CHANGELOG.md) `[1.2.0]`.
 
 ---
 
@@ -167,3 +168,25 @@ the SelfPost image, brought up by the operator when the option is enabled.
 
 A finished outbound path (already implemented). Agreement obtained — see the
 status above.
+
+## Implementation checklist
+
+Target version cut: **`1.4.0`** (MINOR). One commit per step; see
+[development.md](../development.md) § Plan checklists. UI reference:
+[panel-ui inbound mockups](../assets/panel-ui/inbound.html).
+
+- [ ] Migration: inbound domain / recipient / transport tables under `/data` — **Opus**
+- [ ] `INBOUND_RELAY_ENABLE` (default false) in entrypoint + `postfix-config.sh` — **Opus**
+- [ ] `master.cf`: inbound `smtp inet` on 25; separate from 465/587 — **Opus**
+- [ ] Generate `relay_domains`, `transport_maps`, `relay_recipient_maps` (injection-safe) — **Opus**
+- [ ] `smtpd_relay_restrictions` / recipient maps — no open relay, no backscatter — **Opus**
+- [ ] `internal/store` CRUD + validation (domain, host, port) — **Opus**
+- [ ] Panel: list, add, domain detail, recipients, danger zone (mockups) — **Sonnet**
+- [ ] Rate limit + `message_size_limit` on inbound smtpd — **Opus**
+- [ ] Optional `INBOUND_ANTISPAM_MILTER` + compose fragment — **Opus**
+- [ ] DNS MX copy in README/guide; `.env.example` — **Sonnet**
+- [ ] Backup/export inbound config (per plan optional flag) — **Opus**
+- [ ] Unit + handler tests; image build and container smoke — **Opus**
+- [ ] [guide.md](../guide.md) and [security.md](../security.md) — **Sonnet**
+- [ ] Security review inbound path — **Fable**
+- [ ] `go vet`, `go test`, e2e if applicable — **Haiku**