There's a link to a hex file which implements "all Bluetooth services" on this page: https://tech.microbit.org/latest-revision/

The magnetometer services does not work (no compass bearing data is transmitted when notifications are enabled). I think I wrote this sample originally and my guess is that it was not updated when work was done way back to change the accelerometer used and some of the rules for using it. Originally, use of the magnetometer service automatically triggered the calibration service. That's no longer the case afaik and so this sample needs to be changed to make an explicit call to calibrate the magnetometer or something else, equally cunning.

FYI @microbit-mark