fix: hydrate linked GitHub issues

[Sirfetch-d]

Summary

• parse closingIssuesReferences as lightweight GitHub references
• hydrate linked issue title and body through the authenticated gh session
• cap hydration at four concurrent requests while preserving issue order
• skip diff and issue loading for draft and closed pull requests
• bump package metadata and review marker to 0.1.1

Validation

• npx vitest --run test/github-read.test.ts
• npm run check
• npm run test
• npm run pack:check
• read-only /code-review 262 smoke test in private Sirfetch-d/packageauth returned the expected draft skip