Add a fast-fail step that validates artifacthub-pkg.yml before
the expensive build steps. Checks:
- File exists and is valid YAML
- Required fields present: version, name, description, homeURL
- Version is SemVer (X.Y.Z)
- archive-url and archive-checksum annotations are present
- archive-checksum format is sha256:<64 hex chars>
Catches corrupt or incomplete ArtifactHub manifests early in CI
before they reach the release workflow.
Hugh Hackman
cabc4af60d