Ship prebuilt binaries with each release

There is one release, v0.1.0, and it is source-only. So trying BaryoVM means having a Go toolchain, which rules out most of the people who would benefit from a deployment tool. **Scope** - GoReleaser or an equivalent, building for linux/amd64, linux/arm64, darwin/amd64, darwin/arm64 - Attach the binaries to the GitHub release, with checksums - A one-line install in the README **Worth doing properly** - Sign or at least checksum the artefacts. This is a tool people run with SSH access to their servers; "curl | sh" from an unverified binary is a bad habit to teach. - Build reproducibly and stamp the version so `baryovm version` reports something meaningful.