Run from a published image; move source build to docker-compose.build.yaml

docker-compose.yaml now pulls git.goyban.com/goyban/whattodo so it can be used
without the source. publish.sh builds the committed version and pushes it.

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

Dockerfile

@@ -10,7 +10,7 @@ COPY requirements.txt .
 RUN pip install -r requirements.txt
 COPY app ./app
 
-# `docker compose run --rm test`
+# `docker compose -f docker-compose.build.yaml run --rm test`
 FROM base AS test
 COPY requirements-dev.txt .
 RUN pip install -r requirements-dev.txt