feat(sensors): runtime seam for overlay-registered sensor controls

registerSensorControls() lets a private build add SensorControlDef entries for
sensors it ships outside the OSS tree (e.g. the DFRobot Gravity analog family)
so they get the live slider panel; every SENSOR_CONTROLS lookup now goes
through getSensorControl(id) which falls back to the registered map. Dead code
in a pure OSS build, same contract as proBoardRegistry / registerComponentDoc.

frontend/src/components/simulator/SensorControlPanel.tsx

@@ -9,7 +9,7 @@
 import React, { useEffect, useState } from 'react';
 import { useTranslation } from 'react-i18next';
 import {
-  SENSOR_CONTROLS,
+  getSensorControl,
   type SensorControl,
   type SliderControl,
 } from '../../simulation/sensorControlConfig';
@@ -49,7 +49,7 @@ export const SensorControlPanel: React.FC<SensorControlPanelProps> = ({
   onClose,
 }) => {
   const { t } = useTranslation();
-  const def = SENSOR_CONTROLS[metadataId];
+  const def = getSensorControl(metadataId);
 
   // Local slider/button state — hydrated from the registry's last-known
   // values for this componentId (so reopening a sensor or switching between

frontend/src/components/simulator/SimulatorCanvas.tsx

@@ -11,7 +11,7 @@ import { ComponentPickerModal } from '../ComponentPickerModal';
 import { ComponentPropertyDialog } from './ComponentPropertyDialog';
 import { CustomChipDialog } from '../customChips/CustomChipDialog';
 import { SensorControlPanel } from './SensorControlPanel';
-import { SENSOR_CONTROLS } from '../../simulation/sensorControlConfig';
+import { SENSOR_CONTROLS, getSensorControl } from '../../simulation/sensorControlConfig';
 import { DynamicComponent, createComponentFromMetadata } from '../DynamicComponent';
 import { InstrumentComponent } from '../components-instruments/InstrumentComponent';
 import { ComponentRegistry } from '../../services/ComponentRegistry';
@@ -996,7 +996,7 @@ export const SimulatorCanvas = ({ headerSlot }: SimulatorCanvasProps = {}) => {
             const component = componentsRef.current.find((c) => c.id === touchId);
             if (component) {
               if (interactionRunningRef.current) {
-                if (SENSOR_CONTROLS[component.metadataId] !== undefined) {
+                if (getSensorControl(component.metadataId) !== undefined) {
                   setSensorControlComponentId(touchId);
                   setSensorControlMetadataId(component.metadataId);
                 }
@@ -1417,7 +1417,7 @@ export const SimulatorCanvas = ({ headerSlot }: SimulatorCanvasProps = {}) => {
     // panel). Mirrors the touch tap flow above.
     if (interactionRunning) {
       const component = components.find((c) => c.id === componentId);
-      const isSensor = !!component && SENSOR_CONTROLS[component.metadataId] !== undefined;
+      const isSensor = !!component && getSensorControl(component.metadataId) !== undefined;
       if (!isSensor) return;
     }
 
@@ -1710,7 +1710,7 @@ export const SimulatorCanvas = ({ headerSlot }: SimulatorCanvasProps = {}) => {
               // handle its own clicks, so we suppress the property
               // dialog entirely. This is the path that also unblocks
               // wokwi-slide-switch toggling in the digital examples.
-              if (SENSOR_CONTROLS[component.metadataId] !== undefined) {
+              if (getSensorControl(component.metadataId) !== undefined) {
                 setSensorControlComponentId(draggedComponentId);
                 setSensorControlMetadataId(component.metadataId);
               }

frontend/src/simulation/sensorControlConfig.ts

@@ -377,3 +377,20 @@ export const SENSOR_CONTROLS: Record<string, SensorControlDef> = {
     defaultValues: { xAxis: 0, yAxis: 0 },
   },
 };
+
+// ── Overlay seam ─────────────────────────────────────────────────────────────
+// A private build (velxio.com) registers sensor-control definitions for the
+// sensors it ships outside the OSS tree (e.g. the DFRobot Gravity analog
+// family). Same contract as proBoardRegistry / registerComponentDoc: dead code
+// in a pure OSS build. Read every SENSOR_CONTROLS lookup through
+// getSensorControl() so overlay-registered sensors surface their slider panel.
+const proSensorControls: Record<string, SensorControlDef> = {};
+
+export function registerSensorControls(defs: Record<string, SensorControlDef>): void {
+  Object.assign(proSensorControls, defs);
+}
+
+export function getSensorControl(id: string | null | undefined): SensorControlDef | undefined {
+  if (!id) return undefined;
+  return SENSOR_CONTROLS[id] ?? proSensorControls[id];
+}

frontend/src/store/useSimulatorStore.ts

@@ -53,7 +53,7 @@ import {
   updateWires as icUpdateWires,
   setInterconnectRuntime,
 } from '../simulation/Interconnect';
-import { SENSOR_CONTROLS } from '../simulation/sensorControlConfig';
+import { SENSOR_CONTROLS, getSensorControl } from '../simulation/sensorControlConfig';
 import { dispatchSensorUpdate } from '../simulation/SensorUpdateRegistry';
 
 // ── Sensor pre-registration ──────────────────────────────────────────────────
@@ -2150,18 +2150,18 @@ export const useSimulatorStore = create<SimulatorState>((set, get) => {
       // 2.5V) and refreshes the panel's cached value; bumping sensorResetNonce
       // remounts the open SensorControlPanel so its slider snaps back too.
       const sensorComps = get().components.filter(
-        (c) => c.metadataId && SENSOR_CONTROLS[c.metadataId],
+        (c) => c.metadataId && getSensorControl(c.metadataId),
       );
       if (sensorComps.length > 0) {
         set((s) => ({
           components: s.components.map((c) => {
-            const def = c.metadataId ? SENSOR_CONTROLS[c.metadataId] : undefined;
+            const def = getSensorControl(c.metadataId);
             return def ? { ...c, properties: { ...c.properties, ...def.defaultValues } } : c;
           }),
           sensorResetNonce: s.sensorResetNonce + 1,
         }));
         for (const c of sensorComps) {
-          dispatchSensorUpdate(c.id, SENSOR_CONTROLS[c.metadataId].defaultValues);
+          dispatchSensorUpdate(c.id, getSensorControl(c.metadataId)!.defaultValues);
         }
       }
     },