feat: GVs show idx and name when in source list

[pfeerick]

Resolves #2215

Summary of changes:

• on colorlcd, when showing the sources list, if GV has a name, show its index and its name, as opposed to just its index.

This is just proof of concept... the code is still quite ugly...

Before:

After:

I'm pushing this to 2.9 as I want to piggyback and extend this on top of #2085, and also show names of LS when present.