release: 2.5.0: audit stages 1 and 2 - the delivery log and the tenant boundary

Stage 1: a cut queue listing no longer bounces held mail; the reconcile
sweep closes only queued rows, by id, marked "reconcile", and its fate is
measured (delivery_log_days, migration 0007); delivery lines are read at
the head of the line; a renewed TLS certificate is served without a
restart; Health counts the message a hung panel deferred.
Stage 2: logins folded to lower case and unique without regard to case;
the last global administrator kept inside the transaction, users saved
whole; a domain import held to the forms' rules; log rows by domain id
(migration 0008); the 550 reply names no other domain; which key OpenDKIM
signs with, tested. Plus the findings of both reviews of each stage.

Rolled out to the test server as 2.4.2-post.ef18ef2 (the same code):
migrations 0007 and 0008 ran on the live database - schema 8, 68/68 send-log
and 10/10 inbound rows tied to their domain, integrity ok.

CHANGELOG cut; pin 2.5.0 in deploy/docker-compose.yml, README (with the
local-build note), guide; development.md "from pin"; roadmap row and the
recommended order; stages 1 and 2 marked shipped in the plan. No tag (the
owner's command only).

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

docs/development.md

@@ -107,7 +107,7 @@ than the default «meaningful step» rule in [§ Commits and release build](#com
 2. Git tag `vX.Y.Z` and publish the GitHub Release only on explicit request (see
    [§ Release image](#release-image)).
 
-**Planned version cuts** (from pin `2.4.2`; adjust if semver changes mid-track):
+**Planned version cuts** (from pin `2.5.0`; adjust if semver changes mid-track):
 
 | Stage | ID | Cut |
 |---|---|---|