2026-03-25: Knowledge Gaps Port

What Changed

• added src/server/plugins/ports/shared-vectors.ts for reusable embedding parsing, similarity, clustering, and topic-label helpers
• ported Knowledge Gaps into src/server/plugins/ports/knowledge-gaps.ts
• added a thin GET /api/v1/plugins/knowledge-gaps route
• added the codex-side /app/gaps page
• added unit coverage for density classification, bridge-gap detection, and isolated-topic detection

Why It Matters

This port moves codex beyond single-feature convergence and starts building shared analysis infrastructure.

That matters because the same vector helper layer can support:

• topic-evolution
• mind-map-generator
• sentiment and clustering-heavy analysis

Remaining Gaps

• the fetched origin/frain/improve ref still does not expose frain's claimed ports/* files, so codex is still reconstructing some ports from visible route implementations
• Topic Evolution, Sentiment Timeline, and Mind Map Generator still need to land on top of the new shared vector layer
• the current page is a focused codex UI, not the full frain visualization surface yet