The workflow calculates the version with semver-generator, tags the
commit when the version is new, and runs goreleaser. goreleaser ships
two distribution paths: tar.gz binaries for darwin and linux on amd64
and arm64, and a multi-arch ghcr.io container that carries the go,
python3, and C toolchains so the exec evaluators run in-container.
The new llmtest version subcommand reports the stamped build version.