Add column sensitivity release gate

[zergzorg]

Summary

• Adds a self-contained column-sensitivity-release-gate/ module for SCIBASE issue Scientific/Engineering Data & Code Hosting #14.
• Validates hosted dataset columns before public preview, API access, or export.
• Checks direct identifiers, quasi-identifiers, free text redaction review, precise location precision, data-steward approvals, and public sensitive-column budgets.
• Emits deterministic JSON, Markdown, SVG, and MP4 review artifacts.

Non-overlap

This is a column-level sensitivity release gate. It does not duplicate the existing FAIR manifest, artifact package integrity, preview cache, raw/notebook preview, retention/tombstone, model-card lineage, license compatibility, sensitive-file redaction, schema-evolution, data-dictionary, persistent-ID, upload checkpoint, SBOM, or artifact-replica PRs.

Validation

• npm run check
• npm test
• npm run demo
• ffprobe -v error -show_entries format=duration,size -show_entries stream=codec_name,width,height -of default=noprint_wrappers=1 column-sensitivity-release-gate/reports/demo.mp4
• git diff --check
• sensitive term scan for payment/identity/credential markers: no matches

Safety

Synthetic sample data only. No live datasets, credentials, private user data, payout details, or external service calls.

@algora-pbc /claim #14