Agent reference: Diagnostics

Deep subsystem reference for AI assistants. Open this when a task touches diagnostic engines, rows, or tab scoping. Hard rules live in AGENTS.md.

• Engines: src/renderer/lib/diagnostics/; RoutingDiagnosticEngine.ts, RFDiagnosticEngine.ts (includes MeshCore High Companion TX Queue when queueLen > 200), RemediationEngine.ts, ReticulumDiagnosticEngine.ts.
• Store: src/renderer/stores/diagnosticsStore.ts; routing/RF rows, foreign LoRa, MQTT ignore, redundancy.
• Tab scoping: filterDiagnosticRowsForProtocol() — Meshtastic/MeshCore tabs show LoRa rows only; Reticulum tab shows reticulum/* only. Foreign-LoRa tables UI is on Meshtastic and MeshCore tabs (keyed by that protocol’s self node id).
• Extend: adjust DiagnosticRow in src/renderer/lib/types.ts, add detector, wire replaceRoutingRowsFromMap / replaceRfRowsForNode; TTL defaults in diagnosticRows.ts (routing 24h, RF 1h).
• Full reference: ../diagnostics.md.