Context

Skills have a version field in metadata but no version management tooling. There's no way to bump versions, track history, or detect when a skill needs upgrading.

Proposed Changes

• Support skern skill create --version 0.2.0
• Version bumping: skern skill version <name> --bump patch|minor|major
• Optional changelog per skill
• Upgrade detection when comparing registry vs installed versions

References

Analysis item 2.5