Incredibly hacky and convoluted way to draw random stuff on the background. But atleast it is something that works
Added code that can change the background color of lines in the editor
Brought some structure to the madness. Start of ui package that is responsible for showing annotations in the editor itself
Adding hover option for step lines
Finally got the line backgrounds to work in a consistent way
Removed cruft left over from line background experimentations
Added some layout and presentation features
Renamed StepLine stuff to be more consistent
Changed layout to be more like Bret Victor's demo
Draw markers in the column to represent steps