On-screen animations play for empty signals

When the terminal is in EMIT mode and receives an empty command over MQTT (e.g. when the app does not have a command saved for a basic button), the terminal still plays an emit animation even though it does not send any signal.

Steps to reproduce:

1. Connect the terminal to WiFi
2. Open the remote menu in the app
3. Create an empty configuration
4. Press one of the basic buttons (direction, ok, power)