chore: bump ani-skills plugin to 0.6.0

[anistark]

Summary

Type of change

• Add a plugin → please use the add-plugin template instead
• Update a plugin → please use the update-plugin template instead
• Remove a plugin → please use the remove-plugin template instead
• Marketplace / registry change (schema, validation, plugins/ tooling)
• Site / docs change (landing page, README, content)
• CI / workflow / repo tooling
• Bug fix
• Other

Checklist

Uncheck any item that does not apply or has not been completed.

• I have read and understood the contributing guidelines
• Changes are scoped and focused on a single concern
• Tested locally where applicable
• Updated relevant docs (README, site content, etc.) if behavior changed
• Did not hand-edit marketplace.json (it is generated)

[github-actions]

Plugin Validation ❌

Check	Status
Duplicate check	✅ success
Schema validation	❌ failure
Marketplace build	⏭️ skipped

Errors

• plugins/llm-box.json: Invalid or missing source type git. Must be one of: github, url, git-subdir, npm