Add line labels in instance editor

[vadi2]

Is your feature request related to a problem? Please describe. It would be great to see where the errors are just by being able to look at the Instance Editor

Describe the solution you'd like Marker(s) for the line on the right side of the editor - so scrolling the editor will show you where the issues lie.

Hovering over the line marker should explain the issues that are there.

Describe alternatives you've considered An in-line annotation for the issue, so you don't have to hover your mouse over anything?