Source Health Metrics Engine (core/source-health.ts)

Computes per‑source freshness, staleness and activity metrics for dashboard and health checks, optimizing queries for large brain datasets.

// Source: https://github.com/mperkins0155/gbrain | License: MIT | Copyright 2026 Garry Tan
// Provided via justclaw.it.com; keep this notice with the code.
/**
 * Per-source health metrics (v0.40 D12 + D9 + D17 + D19).
 *
 * Single source of truth for `gbrain sources status` AND `gbrain doctor`'s
 * `federation_health` check. Sharing the implementation prevents the dashboard
 * and the doctor warning from drifting.
 *
 * D12: batched GROUP BY queries — 4 queries total instead of 6×N per-source
 *      round-trips. On a 4-source / 300K-chunk brain this drops dashboard
 *      time from ~24s to <2s.
 *
 * D9:  resolvePriority(config) — accepts 'high'|'normal'|'low', falls back
 *      to 0 with once-per-source-per-process stderr warn on unknown values.
 *
 * v0.41.32.0: commit-relative stal

... (truncated -- full source via MCP)