Add knowledge graph conflict arbiter

[FeeeeelixWong]

/claim #17

Summary

• add a self-contained scientific knowledge graph relationship conflict arbiter
• score support/refute graph edges by confidence, evidence type, citation count, and freshness
• quarantine close contradictory claims, suppress dependent recommendations, and generate curator actions with audit hashes
• include synthetic graph data, requirement mapping, tests, CLI demo, SVG, and short MP4 demo

Why this is scoped to issue #17

This focuses on graph-quality control after entity/relationship extraction: deciding whether extracted relationships are trustworthy enough for graph search, entity pages, and AI recommendations. It avoids duplicating broad extractors, graph navigators, link-audit modules, ontology-drift migration controls, or knowledge-gap explorers already submitted by others.

Demo

• knowledge-graph-conflict-arbiter/docs/demo.mp4
• knowledge-graph-conflict-arbiter/docs/demo.svg

Verification

• npm run check
• npm test
• npm run demo
• ffprobe knowledge-graph-conflict-arbiter/docs/demo.mp4
• git diff --check