release: 2.9.1: log panes wrap on a phone

Cut without asking, as the owner said on 2026-10-15, for his report of
2026-10-16 (two scroll bars over a message's Delivery log on his phone).

Log panes wrap their lines under their start instead of scrolling
sideways (216f366 design, bd21ff0 code): the Delivery log of a message,
System log, the queue's listing. go vet, go test (26 packages) and make
e2e passed on the test server for that tree. No migration, schema 11.
The inbound-upstream-result mockup and plan (5348330, 295d72e) ride
along; its code follows for 2.10.0.

CHANGELOG [2.9.1]; pins in deploy/docker-compose.yml, README and the
guide (pin, build, the sample restore message); development's "from pin"
and row 31. 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=2.9.0 \
->   -t ghcr.io/mixeme/selfpost:2.9.0 .
+> docker build -f build/Dockerfile --build-arg VERSION=2.9.1 \
+>   -t ghcr.io/mixeme/selfpost:2.9.1 .
 > ```
 
 ```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:2.9.0
+  ghcr.io/mixeme/selfpost:2.9.1
 ```
 
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