The change here is to make it easier for the consumer to debug the api.
Such that they can `match` on individual errors instead of having to
parse text.
eyre is convenient, but mostly from a consumers perspective
This adds the first iteration of multi platform ci. This is the lowest level of testing added: pinned all the way to nightly. Next up will be macos, then musl and arm. And lastly windows. Each will probably require special handling, especially because of how cross and qemu interacts with the dagger-engine and docker.
