Formalize Judgment Craft release operations

[perhapsspy]

Summary

• add a dependency-free plugin validator and focused regression tests
• add CI and immutable tag-triggered GitHub Release workflow
• define product, contribution, SemVer, marketplace, and rollback ownership
• add Korean/English public documentation and repository ownership settings

Boundary

• plugins/judgment-craft/** remains byte-for-byte unchanged
• no multi-source lock, sync, generated snapshot, or architecture layer is introduced

Validation

• 8 unit tests pass
• plugin validator passes
• --release-tag v0.1.0 passes
• canonical plugin subtree diff is empty