chore(design): track recoverable Penpot snapshots

[bntvllnt]

Native Penpot exports need a recoverable version record. Add snapshot manifests with per-file revisions and content hashes, a dependency-free integrity checker, and recovery instructions. The publication record explicitly states that native archives remain local and their proposed GitHub release upload awaits approval.

Validation on cdec52f704502851f69ac54992dbe10df813d31c:

• 11 checker tests pass, including corrupt/missing assets, incorrect inventories, CRC failure and non-overwrite behavior.
• Both local native exports pass SHA-256, CRC and inventory verification. Documentation links, JSON records and Git diff checks pass.
• CI run passed all Quality Gates (lint, atomic levels, typecheck, build, workspace tests and registry checks), Native Package Gates and E2E tests. Code and archive receipts are unchanged by the final documentation-only commit.

The proposed native-archive upload is pending and no downloaded-copy or new native-restore verification is claimed.

Closes #544