Documents the exact Prisma query per dashboard figure, the one new durable table this feature needs (ErrorCodeLookup — 014's own equivalent metric is process-lifetime, unusable for a historical report), the "no data -> null, never NaN" convention, and why the AI dashboard's confidence distribution deliberately uses the system-default threshold rather than resolving a per-diagnosis policy (AIDiagnosis has no reliable FK back to which policy applied). Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>