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/measurement/measurementHandlers.js

@@ -0,0 +1,134 @@
+/**
+ * Centralised measurement update routing for rotatingMachine.
+ *
+ * Wraps the four measurement types coming from child measurement nodes
+ * (flow / power / temperature / pressure) and dispatches each to the
+ * appropriate handler. Pressure is delegated to the host's pressureRouter
+ * (built in P5.4); the other three are normalised + written + drift-tracked
+ * here.
+ *
+ * The handlers reach back into the host for `_resolveMeasurementUnit`,
+ * `_updateMetricDrift`, `_updatePredictionHealth`, `updatePosition` and the
+ * measurements container. Behaviour is preserved 1:1 from the original
+ * specificClass methods.
+ */
+
+class MeasurementHandlers {
+  constructor(ctx) {
+    if (!ctx || !ctx.host) {
+      throw new Error('MeasurementHandlers: ctx.host is required');
+    }
+    this.host = ctx.host;
+    this.logger = ctx.logger || ctx.host.logger;
+  }
+
+  /**
+   * Single entry point used by child-measurement event listeners.
+   * Unknown types warn and fall back to a no-op position refresh so a
+   * mis-configured child can't silently break the FSM tick.
+   */
+  dispatch(measurementType, value, position, context = {}) {
+    switch (measurementType) {
+      case 'pressure':
+        return this.host.updateMeasuredPressure(value, position, context);
+      case 'flow':
+        return this.updateMeasuredFlow(value, position, context);
+      case 'power':
+        return this.updateMeasuredPower(value, position, context);
+      case 'temperature':
+        return this.updateMeasuredTemperature(value, position, context);
+      default:
+        this.logger.warn(`No handler for measurement type: ${measurementType}`);
+        return this.host.updatePosition();
+    }
+  }
+
+  updateMeasuredTemperature(value, position, context = {}) {
+    const host = this.host;
+    this.logger.debug(
+      `Temperature update: ${value} at ${position} from ${context.childName || 'child'} (${context.childId || 'unknown-id'})`,
+    );
+    let unit;
+    try {
+      unit = host._resolveMeasurementUnit('temperature', context.unit);
+    } catch (error) {
+      this.logger.warn(`Rejected temperature update: ${error.message}`);
+      return;
+    }
+    host.measurements
+      .type('temperature')
+      .variant('measured')
+      .position(position || 'atEquipment')
+      .child(context.childId)
+      .value(value, context.timestamp, unit);
+  }
+
+  updateMeasuredFlow(value, position, context = {}) {
+    const host = this.host;
+    if (!host._isOperationalState()) {
+      this.logger.warn(`Machine not operational, skipping flow update from ${context.childName || 'unknown'}`);
+      return;
+    }
+    this.logger.debug(`Flow update: ${value} at ${position} from ${context.childName || 'child'}`);
+    let unit;
+    try {
+      unit = host._resolveMeasurementUnit('flow', context.unit);
+    } catch (error) {
+      this.logger.warn(`Rejected flow update: ${error.message}`);
+      return;
+    }
+
+    host.measurements
+      .type('flow').variant('measured').position(position).child(context.childId)
+      .value(value, context.timestamp, unit);
+
+    if (host.predictFlow) {
+      const canonical = host.unitPolicy.canonical.flow;
+      const predicted = host.predictFlow.outputY || 0;
+      host.measurements.type('flow').variant('predicted').position('downstream')
+        .value(predicted, Date.now(), canonical);
+      host.measurements.type('flow').variant('predicted').position('atEquipment')
+        .value(predicted, Date.now(), canonical);
+    }
+
+    const measuredCanonical = host.measurements
+      .type('flow').variant('measured').position(position)
+      .getCurrentValue(host.unitPolicy.canonical.flow);
+
+    host._updateMetricDrift('flow', measuredCanonical, context);
+    host._updatePredictionHealth();
+  }
+
+  updateMeasuredPower(value, position, context = {}) {
+    const host = this.host;
+    if (!host._isOperationalState()) {
+      this.logger.warn(`Machine not operational, skipping power update from ${context.childName || 'unknown'}`);
+      return;
+    }
+    this.logger.debug(`Power update: ${value} at ${position} from ${context.childName || 'child'}`);
+    let unit;
+    try {
+      unit = host._resolveMeasurementUnit('power', context.unit);
+    } catch (error) {
+      this.logger.warn(`Rejected power update: ${error.message}`);
+      return;
+    }
+    host.measurements
+      .type('power').variant('measured').position(position).child(context.childId)
+      .value(value, context.timestamp, unit);
+
+    if (host.predictPower) {
+      host.measurements.type('power').variant('predicted').position('atEquipment')
+        .value(host.predictPower.outputY || 0, Date.now(), host.unitPolicy.canonical.power);
+    }
+
+    const measuredCanonical = host.measurements
+      .type('power').variant('measured').position(position)
+      .getCurrentValue(host.unitPolicy.canonical.power);
+
+    host._updateMetricDrift('power', measuredCanonical, context);
+    host._updatePredictionHealth();
+  }
+}
+
+module.exports = MeasurementHandlers;