readManufacturingSample

INTERNAL TESTING ONLY, DO NOT USE Issues a single GATT read on the manufacturing data characteristic (6C4D, see UUIDUtils.ManufacturingCharUUID). Results are delivered to BlueLinkEventListener.onCharacteristicRead after BlueLinkPeripheralListenerImpl routes 6C4D payloads without treating them as heartbeat protobuf. The Android manufacturing bridge polls this on a fixed interval (e.g. 100ms), buffers payloads, and sends them to the Pi in one batch when the manufacturing session ends.