release: 2.5.3: audit stage 3 - persistence and restore

Cut without asking, as the owner said on 2026-10-15: "Вопросы про резку не
задавай, просто режь."

A restore is ended by its Resync: the manifest stays until the first start
has regenerated the maps (M1). Every archive ends with data/contents.json and
the first start after a restore compares /data with it before it opens the
database: half an archive, a damaged file, a journal left beside the
database is refused, named. The entrypoint hands every map under
/data/postfix to the panel (a restore unpacked as root left the DMARC maps
unreadable - found by the review). Migration 0010: the send log's sweep,
refusal-line check, level-2 count and pages each by its index, pinned by
EXPLAIN tests on the statements the store runs (M2). The backup CLI refuses
a missing database (M3) and a password under 12 (M5), writes -o whole,
checks -decrypt's password before the output (L1), warns of what it leaves
out and refuses an empty certs/ (L2). An encrypted file may ask scrypt for
128 MiB at most, r <= 64, p <= 2, and nothing may follow its last chunk
(M4, L3). TRUSTED_PROXY_CIDR's bare ::ffff:a.b.c.d is one host (L4). Maps
are durable across a power loss: the directory is synced (L7). Commits
8e3241e, 508ac96, 242515c, 76b21b3.

Rolled out to the test server as 2.5.2-post.76b21b3 (the same code):
migration 0010 applied, schema 10, the four new indexes present; all
programs RUNNING, Postfix with its three milters, nothing in the logs. On
the live container: a CLI backup ends with data/contents.json, a wrong
SELFPOST_DB_PATH is refused and creates nothing, a short password is
refused.

CHANGELOG cut; pin 2.5.3 in deploy/docker-compose.yml, README, guide (and
its sample restore message); development.md "from pin" and the stage's row;
roadmap row and recommended order; stage 3 marked shipped in the plan. No
tag.

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

docs/roadmap.md

@@ -42,7 +42,7 @@ in `git log` and [CHANGELOG.md](../CHANGELOG.md).
 | from-header-binding | Hold a message's `From:` header against the application that sends it | shipped `2.4.0` | 9/9 | [plans/from-header-binding.md](plans/from-header-binding.md) |
 | panel-redesign | Panel redesign (accepted mockups, design contract) | shipped `2.0.0` | 27/27 | [plans/panel-redesign.md](plans/panel-redesign.md) |
 | schema-squash | Squash SQLite migrations into a 2.x baseline | built in panel-redesign (stage 1) | — | [plans/panel-redesign.md](plans/panel-redesign.md) |
-| audit-2026-10-12 | Follow-ups of the 2026-10-12 full-tree code audit, seven stages | in progress (stage 0 shipped `2.4.2`, stages 1+2 `2.5.0`, 2b `2.5.1`, 2c `2.5.2`; next stage 3 → `2.5.3`) | 55/81 | [audit-2026-10-12.md](audit-2026-10-12.md) |
+| audit-2026-10-12 | Follow-ups of the 2026-10-12 full-tree code audit, seven stages | in progress (stage 0 shipped `2.4.2`, stages 1+2 `2.5.0`, 2b `2.5.1`, 2c `2.5.2`, 3 `2.5.3`; next stage 4 → `2.5.4`) | 55/81 | [audit-2026-10-12.md](audit-2026-10-12.md) |
 
 **Recommended order** (not binding; owner, 2026-10-09: feature order follows
 development convenience): **panel-redesign** shipped as `2.0.0` (2026-10-11) and
@@ -51,8 +51,8 @@ kit — styling its two screens once instead of twice. **delivery-log-storage**
 shipped as `2.2.0` the same day, **panel-notifications** as `2.3.0` and
 **from-header-binding** as `2.4.0`. Stage 0 of
 [audit-2026-10-12](audit-2026-10-12.md) shipped as `2.4.2` (2026-10-14), its
-stages 1 and 2 as `2.5.0` the same day, stage 2b as `2.5.1`, and stage 2c as
-`2.5.2` (2026-10-15).
+stages 1 and 2 as `2.5.0` the same day, stage 2b as `2.5.1`, stage 2c as
+`2.5.2` (2026-10-15), and stage 3 as `2.5.3` the same day.
 Nothing is agreed after it: every remaining
 item is a candidate. panel-docs shipped in
 [CHANGELOG.md](../CHANGELOG.md) `[1.8.0]`; dmarc-reports in `[1.7.0]`