- cli: the subcommand is optional; without one, sausage runs ./world and
runs init first when ./world is not a world yet (test: cli/tests/cli.rs).
- flake: .#loop without a folder runs bare sausage.
- README: nix run git+https://gitea.surma.technology/surma/sausage(#loop),
clone only for working on Sausage.
