P5 wave 1: extract rotatingMachine concerns into focused modules

src/curves/         loader + normalizer (with cross-pressure anomaly
                      detection) + reverseCurve helper
  src/prediction/     predictors (predictFlow/Power/Ctrl) +
                      groupPredictors (lazy group-scope views) +
                      OperatingPoint (pressure-driven prediction setpoints)
  src/drift/          DriftAssessor (per-metric drift) + PredictionHealth
                      (composes flow/power/pressure into HealthStatus +
                      confidence sibling — see OPEN_QUESTIONS 2026-05-10)
  src/pressure/       VirtualPressureChildren (dashboard-sim) +
                      PressureInitialization (real-vs-virtual tracking) +
                      PressureRouter (dispatches by position)
  src/state/          stateBindings (state.emitter listener helper) +
                      isOperationalState
  src/measurement/    measurementHandlers (dispatcher for flow/power/temp/pressure)
  src/flow/           flowController (handleInput body — execSequence,
                      execMovement, flowMovement, emergencystop)
  src/display/        workingCurves (showWorkingCurves + showCoG admin)
  src/commands/       canonical names: set.mode, cmd.startup/shutdown/estop,
                      set.setpoint, set.flow-setpoint,
                      data.simulate-measurement, query.curves, query.cog,
                      child.register. execSequence demuxes by payload.action
                      to canonical cmd.* handlers.
  CONTRACT.md         inputs/outputs/events/children surface

110 basic tests pass (100 new + 10 pre-existing).
specificClass.js / nodeClass.js untouched — integration in P5 wave 2.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/pressure/virtualChildren.js

@@ -0,0 +1,92 @@
+'use strict';
+
+const { MeasurementContainer } = require('generalFunctions');
+
+/**
+ * VirtualPressureChildren — builds two dashboard-sim children backed
+ * by their own MeasurementContainer (upstream + downstream). Children
+ * are signed as belonging to a parent machine via `setParentRef`.
+ *
+ * Extracted from rotatingMachine specificClass._initVirtualPressureChildren.
+ */
+
+const DEFAULT_IDS = {
+  upstream: 'dashboard-sim-upstream',
+  downstream: 'dashboard-sim-downstream',
+};
+
+class VirtualPressureChildren {
+  /**
+   * @param {object} opts
+   *   - logger: pass-through to MeasurementContainer
+   *   - unitPolicy: { canonical, output }
+   *   - parentRef: object to use as parent for setParentRef (optional)
+   *   - ids: override the default { upstream, downstream } id pair (optional)
+   */
+  constructor({ logger, unitPolicy, parentRef = null, ids = DEFAULT_IDS } = {}) {
+    this.logger = logger || { warn() {}, debug() {} };
+    this.unitPolicy = unitPolicy;
+    this.parentRef = parentRef;
+    this.ids = { ...DEFAULT_IDS, ...(ids || {}) };
+  }
+
+  /**
+   * @returns {{ upstream: VirtualChild, downstream: VirtualChild }}
+   *   Each child = { config: { general, functionality, asset }, measurements }.
+   */
+  build() {
+    return {
+      upstream: this._createChild('upstream'),
+      downstream: this._createChild('downstream'),
+    };
+  }
+
+  _createChild(position) {
+    const id = this.ids[position];
+    const name = `dashboard-sim-${position}`;
+    const measurements = new MeasurementContainer({
+      autoConvert: true,
+      defaultUnits: this._unitMap('output'),
+      preferredUnits: this._unitMap('output'),
+      canonicalUnits: this.unitPolicy?.canonical,
+      storeCanonical: true,
+      strictUnitValidation: true,
+      throwOnInvalidUnit: true,
+      requireUnitForTypes: ['pressure'],
+    }, this.logger);
+
+    if (typeof measurements.setChildId === 'function') measurements.setChildId(id);
+    if (typeof measurements.setChildName === 'function') measurements.setChildName(name);
+    if (this.parentRef && typeof measurements.setParentRef === 'function') {
+      measurements.setParentRef(this.parentRef);
+    }
+
+    return {
+      config: {
+        general: { id, name },
+        functionality: {
+          softwareType: 'measurement',
+          positionVsParent: position,
+        },
+        asset: {
+          type: 'pressure',
+          unit: this.unitPolicy?.output?.pressure,
+        },
+      },
+      measurements,
+    };
+  }
+
+  _unitMap(section) {
+    const src = this.unitPolicy?.[section] || {};
+    return {
+      pressure: src.pressure,
+      flow: src.flow,
+      power: src.power,
+      temperature: src.temperature,
+    };
+  }
+}
+
+VirtualPressureChildren.DEFAULT_IDS = DEFAULT_IDS;
+module.exports = VirtualPressureChildren;