[CG-12] Navigator app: browse Insights from the SQLite database

[jgrodziski]

Priority: P1
Owner: Jérémie (hands the DB over) · David

Context

The Broadleaf Insights run produced a ~50 MB JSONL, converted to a SQLite database so that a skill can traverse it. The Navigator app (left-hand Tree Panel, served together with the city by serve) does not expose Insights yet.

Acceptance criteria

• Navigator reads the SQLite Insights DB
• Insight text visible per entity in the Tree Panel / detail view
• Keep the deterministic-walk output as a separate file from the LLM Insights (already the case — keep it that way)

---

Source: CodeGraph backlog extracted from the 2026-09-21 weekly (David / Jérémie).