feat(devices): radar presence input + button-light output on the controller

Model the entry button (I1) and a Hikvision radar (I2) as named children of the
access controller, and drive the button's 12V lamp on a spare relay.

- Radar = the existing relays[].presenceInput one-car-one-ticket gate, now labelled
  presenceKind: loop|radar. A radar may idle opposite the button, so add a per-input
  active-level override: relays[].presenceActiveLow -> driver inputActiveLow set,
  inverting just that terminal (pure helper inputActive()). The Dingtian has one
  board-wide resting level otherwise.
- AuxOutputDevice.setAux(channel,on) capability on the device interface (Dingtian
  latch) so business logic drives a NON-barrier lamp through the interface. Barriers
  still only pulseOpen — barrier-not-a-door preserved.
- ButtonLightController: subscribes to the radar input edge + the camera lane status
  and drives a 3-state lamp — radar+car=solid, radar-only=blink (~1Hz), else off.
  Fails OFF on host loss/error; de-duped. A radar detection never opens a barrier on
  its own (advisory; threat model).
- SetupWizard: presence kind + active-low + a button-light relay picker; sq+en i18n.

Tests: button-light.test.ts (truth table + blink + fail-OFF + de-dupe),
access-dingtian.test.ts (active-level inversion). Workspace build+lint+test green
(158 server tests). Wiki: hikvision-radar, button-light-indicator + updates.

Claude-Session: https://claude.ai/code/session_01Xcm6ikLgGoCxxHrxtjkk5V

packages/devices/src/interfaces.ts

@@ -35,6 +35,23 @@ export interface AccessControlDevice extends Device {
   getDoorStatus(doorId: number): Promise<"open" | "closed">;
 }
 
+// --- Auxiliary outputs (non-barrier latched signals) ---------------------
+// Optional capability for controllers with SPARE relays wired to something that
+// is NOT a barrier — a button lamp, a "wait"/"go" sign. setAux LATCHES the output
+// on or off and holds it (unlike pulseOpen, which is momentary). The
+// barrier-not-a-door rule does NOT apply here: this output never gates a vehicle,
+// so holding/blinking it is fine. Business logic drives indicators through THIS,
+// never the driver's own relay methods. See wiki/concepts/button-light-indicator.md.
+export interface AuxOutputDevice {
+  /** Latch an auxiliary output on/off. 1-based channel (a spare relay). */
+  setAux(channel: number, on: boolean): Promise<void>;
+}
+
+/** Feature-detect the aux-output capability on a built device adapter. */
+export function hasAuxOutput(d: unknown): d is AuxOutputDevice {
+  return typeof (d as Partial<AuxOutputDevice>)?.setAux === "function";
+}
+
 // --- Inputs (buttons / dry contacts) -------------------------------------
 // Optional capability for controllers that expose host-readable inputs SEPARATE
 // from their relays — e.g. the Dingtian board. This is what enables host-in-the-