ci: check ClawHub package version

[BenKalsky]

Summary

• Add a ClawHub version check script comparing package.json with the published ClawHub package latestVersion
• Add a Registry sync workflow that runs on main/package changes, schedule, and manual dispatch
• Keep PR CI green while surfacing post-release drift on main

Test Plan

• npm ci
• npm run typecheck
• npm test
• npm pack --dry-run
• CLAWHUB_VERSION_CHECK_MODE=warn npm run check:clawhub
• npm run check:clawhub exits non-zero while ClawHub is still 0.1.1 and package.json is 0.1.2
• YAML parsed for ci.yml, publish.yml, registry-sync.yml

Related: Paperclip DEE-51