How does TuyaOS report the MCU version number?

UINT_T attr_num = 3;
GW_ATTACH_ATTR_T attr[3] = {
  {
    .tp = DEV_NM_NOT_ATH_SNGL, // MCU module
    .ver = "1.0.0"
  },
  {
    .tp = DEV_BLE_SNGL, // Bluetooth module
    .ver = "2.0.0"
  },
  {
    .tp = DEV_ATTACH_MOD_1, // Voice module (custom tp, needs to be consistent with IoT frontend configuration)
    .ver = "3.0.0"
  }
};