[GUI] Fix energy monitoring when a GPU lacks power readings

apps/host/server/energy-meter.mjs

@@ -4,6 +4,12 @@
  */
 const meter = { wh: 0, at: 0 };
 
+/** Sum the cards that report power. An unmetered iGPU must not hide a measured discrete GPU. */
+export function reportedPower(readings, key = 'powerW') {
+  const values = readings.map(gpu => gpu[key]).filter(value => typeof value === 'number' && Number.isFinite(value) && value >= 0);
+  return values.length ? values.reduce((total, value) => total + value, 0) : null;
+}
+
 export function addEnergy(powerW, at) {
   const dt = meter.at ? Math.min((at - meter.at) / 1000, 5) : 0;
   meter.at = at;

apps/host/server/monitor.mjs

@@ -5,7 +5,7 @@ import { readGpuTelemetry, gpuMemoryTotals } from './device-probes.mjs';
 import { createSystemSampler } from './system-telemetry.mjs';
 import { sensorPace, WATCH_MS } from './sensor-pace.mjs';
 import { readTemperatures } from './temperature-telemetry.mjs';
-import { addEnergy, energyWh } from './energy-meter.mjs';
+import { addEnergy, energyWh, reportedPower } from './energy-meter.mjs';
 import { state as servingState } from './serving.mjs';
 import { originalDashboard } from './monitor-dashboard.mjs';
 import { get as getStore } from './store.mjs';
@@ -93,7 +93,7 @@ function hardwareSnapshot() {
     vramTotalGb:memory.total,
     ramUsedGb:systemReading?.ramUsedGb??null,ramTotalGb:systemReading?.ramTotalGb??hw.ramTotalGb,
     gpuTempC:aggregate(readings,'temperatureC','max'),tempLimitC:hw.tempLimitC,
-    powerW:aggregate(readings,'powerW'),powerLimitW:aggregate(readings,'powerLimitW'),
+    powerW:reportedPower(readings),powerLimitW:reportedPower(readings,'powerLimitW'),
     pcieRxMbs:aggregate(readings,'pcieRxMbs'),
     cpuTempC:demo?54:temperatures.cpuTempC,ssdTempC:demo?41:temperatures.ssdTempC,energyWh:round(energyWh(),3),
     diskReadGbs:systemReading?.diskReadGbs??null,diskWriteMbs:systemReading?.diskWriteMbs??null,

apps/host/tests/energy-meter.test.mjs

@@ -0,0 +1,20 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { addEnergy, reportedPower } from '../server/energy-meter.mjs';
+
+test('an unmetered iGPU does not prevent energy accumulation from a metered GPU', () => {
+  const readings = [
+    { id: 'GPU-discrete', powerW: 72, powerLimitW: 575 },
+    { id: 'GPU-integrated', powerW: null, powerLimitW: null },
+  ];
+  assert.equal(reportedPower(readings), 72);
+  assert.equal(reportedPower(readings, 'powerLimitW'), 575);
+  const start = addEnergy(reportedPower(readings), 1_000);
+  assert.equal(addEnergy(reportedPower(readings), 6_000) - start, 0.1);
+});
+
+test('power remains unavailable when no GPU reports it, and multiple readings are summed', () => {
+  assert.equal(reportedPower([]), null);
+  assert.equal(reportedPower([{ powerW: null }, { powerW: NaN }]), null);
+  assert.equal(reportedPower([{ powerW: 20 }, { powerW: 30 }]), 50);
+});