Add knowledge graph ethics provenance guard

[zergzorg]

@algora-pbc /claim #17

Summary

• Adds a self-contained knowledge-graph ethics provenance guard for issue Scientific Knowledge Graph Integration #17.
• Screens recommendation evidence for IRB approval, consent scope, restricted data use, biosafety clearance, animal-care evidence, dual-use review, and stale/retracted provenance before a recommendation is shown.
• Emits deterministic JSON-LD style review packets, curator actions, an audit digest, and demo artifacts for downstream review.

Scope boundaries

• Uses synthetic data only.
• Does not add a new external provider integration, account flow, API key, payment step, or private-data dependency.
• Designed as a narrow ethics/provenance review slice so it does not overlap with broad extractor, ontology, navigator, link-audit, or relationship-conflict attempts.

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 reports/demo.mp4
• git diff --check