One command fetches the vendored files from prompts at a commit, keeps a repo's own entries, commits and pushes. An entry above a file's closing comment that the canonical file lacks stops it before it writes. A run with nothing to commit still pushes, so a retry delivers a failed push. The canonical .dockerignore gains the closing comment the script needs. test/update-policy.sh tests the script in the Dockerfile test phase.
Model: opus-5-5
sneak