this complements #18 but is different.

This proposal is for including a compose file to make it easy to spin up a local postgres DB and s3-compatible storage so that there is something for the app to connect to without relying on CSH credentials

I basically have this in a dev-quality state locally (using minio and postgres) but am curious if this would be desirable to try and document and include in the repo as part of a complete breakfast dev environment