Really frustrating trying to find this out.
in the “Arrange” window NOT the main menu….
view->configure track headers-> ..and tick the box that says track color bars.
To actually ASSIGN a colour, select the track, view->colors and a palette will appear, select the colour and you are done.
No, you can’t tell Logic to assign colours to any kind of format, unless you set it up in the environment to do so. Obviously this is far too useful.