Add decorators to current line for run by line

[rchiodo]

Should be able to:

• Add line color
• Add glyph in the margin (need icon? hopefully can use codicons)

See:
https://code.visualstudio.com/api/references/vscode-api#DecorationRenderOptions

[DavidKutu]

I think this is done

[rchiodo]

I assume Rob is handling the IP indicator? We used to hack that in before, but since VS code knows about the debugging it will show the ip indicator?

Actually if that's the case, maybe you didn't need to do anything here? Cause VS code would be putting the decorator too.

[DavidKutu]

what's the IP indicator?

[rchiodo]

The little arrow that shows what line you're currently running.

IP stands for instruction pointer. In C++ land it's called that and there's a register on the CPU that usually stores the address of the IP called rip

https://en.wikipedia.org/wiki/Program_counter