Menu doesn't close after Serial API Calibration

[jakemcivor]

The Serial API can be used to trigger a full calibration, which triggers messages on the Menu. After the calibration is complete, the LipSync will go back into operating mode but the menu remains on. It doesn't time out, nor can the user navigate the menu to exit.

The user can re-activate the menu using the button / switch / long puff to regain access and close the menu normally.