microbit vision webapp step 4: combine vision and bluetooth
https://ferryzhou.github.io/nezha-ble/hands-ble/index.htm
https://github.com/ferryzhou/nezha-ble/tree/main/hands-ble
basically, in onResults function, encode landmarks coordinates into a string, and send to bluetooth uart interface, and in makecode microbit code, receive string and decode.
the next step is to make the hardware that can mount the phone and can move.