release: 2.6.1: port 25 ends DATA only at CRLF.CRLF

Cut without asking, as the owner said on 2026-10-15.

The inbound relay's smtp/inet listener sets
smtpd_forbid_bare_newline=normalize, the SMTP-smuggling defence Postfix
3.7.11 leaves off (aaa9412, port25-bare-newline, the first of the three
rows from own-mta-builds).

Rolled out to the test server as 2.6.0-post.aaa9412 (the same code): the
container healthy, every program RUNNING; the server runs the inbound
relay, and postconf -P shows smtp/inet/smtpd_forbid_bare_newline =
normalize next to syslog_name postfix/inbound; no warning or fatal in
docker logs. No migration, schema 11.

CHANGELOG cut; pin 2.6.1 in deploy/docker-compose.yml, README, guide (and
its sample restore message); development.md "from pin" and the row;
roadmap row shipped and the recommended order. No tag.

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

README.md

@@ -112,8 +112,8 @@ outbound mail will not reach the real internet without DNS, PTR, and port 25.
 > local image and pulls nothing:
 >
 > ```sh
-> docker build -f build/Dockerfile --build-arg VERSION=2.6.0 \
->   -t ghcr.io/mixeme/selfpost:2.6.0 .
+> docker build -f build/Dockerfile --build-arg VERSION=2.6.1 \
+>   -t ghcr.io/mixeme/selfpost:2.6.1 .
 > ```
 
 ```sh
@@ -122,7 +122,7 @@ docker run --rm -d --name selfpost-try \
   -e SELFPOST_HOSTNAME=mail.local.test \
   -e PANEL_COOKIE_SECURE=false \
   -v selfpost-try-data:/data \
-  ghcr.io/mixeme/selfpost:2.6.0
+  ghcr.io/mixeme/selfpost:2.6.1
 ```
 
 **Get the setup URL** (pick one):