feat(control_plane): apply light standby hardware policy

components/control_plane/include/control_plane.h

@@ -142,9 +142,9 @@ esp_err_t control_plane_prepare_runtime_storage(void);
 /**
  * @brief Start the control-plane owned light-standby coordinator.
  *
- * The coordinator tracks one inactivity deadline for the full runtime. Phase
- * one records state transitions only; hardware power policies are attached in
- * later phases. Repeated starts are idempotent.
+ * The coordinator tracks one inactivity deadline for the full runtime and
+ * applies configured local hardware power policies. Repeated starts are
+ * idempotent.
  */
 esp_err_t control_plane_light_standby_start(void);
 
@@ -159,8 +159,9 @@ esp_err_t control_plane_light_standby_stop(int timeout_ms);
 /**
  * @brief Record user activity and return the coordinator to ACTIVE state.
  *
- * This call is non-blocking and safe from control-plane worker tasks. It must
- * not be called directly from an ISR.
+ * If hardware is in light standby, this call restores configured hardware
+ * before returning. Transition serialization is bounded; the API must not be
+ * called directly from an ISR.
  */
 esp_err_t control_plane_light_standby_record_activity(
         control_plane_light_standby_activity_t activity);