Add embargoed data license guard

[drsteinerdj]

Summary

• Add a self-contained embargoed-data-license-guard module for Revenue Infrastructure issue Revenue Infrastructure #20
• Validate whether anonymized research metadata/data-licensing exports can be released while embargo, exclusivity, cohort-size, consent, license-tier, release-term, and snapshot-freshness obligations are satisfied
• Include synthetic packets, deterministic RELEASE / REVIEW / HOLD decisions, dependency-free tests, CLI demo, and reviewer artifacts

Bounty fit

/claim #20

This targets the data licensing / analytics revenue stream in issue #20. It is distinct from the visible subscription, usage metering, payment-dispute, grant, FX, tax, event-sponsorship, analytics-seat, data-product freshness, and privacy-safe licensing slices by focusing specifically on embargoed data licensing release control before delivery or invoicing.

No live customer data, private research content, payment processors, credentials, or external APIs are used.

Verification

From embargoed-data-license-guard/:

• npm test -> license guard tests passed
• npm run demo

From repo root:

• git diff --check

Reviewer artifacts

• embargoed-data-license-guard/artifacts/demo-output.json
• embargoed-data-license-guard/artifacts/demo-report.md
• embargoed-data-license-guard/artifacts/release-summary.svg