The docker.io apt package doesn't ship the compose plugin, and the
npm docker-compose package is an unrelated legacy tool that doesn't
provide the 'docker compose' CLI subcommand. Install the official
compose v2 binary as a docker CLI plugin instead.
Base image for the gitea-act-runner build environment, includes
Docker CLI and docker-compose for CI jobs that need to build/push
containers, plus corepack for yarn/pnpm support."