The "Regenerate for current view" build was failing in production with
"could not run 'pmtiles'" — go-pmtiles was never actually installed
anywhere, just documented as something a developer runs by hand
locally (docs/development.adoc). Installs the static Linux binary from
go-pmtiles' own GitHub releases, architecture-matched via dpkg rather
than hardcoded amd64.
Verified the exact download/extract/exec sequence end-to-end outside
Docker (no daemon available in this sandbox to run a real build).
Containerize the app (Dockerfile, docker-compose.yaml) and add a CI
deploy job that syncs the checkout to /srv/docker/maptool and runs
docker compose directly, using the runner's new "host" execution
label to reach the host's Docker daemon and filesystem.