Add visuals to node tooltips

[AlexBxl]

Overview

Would be super useful to show a simple 2-node example when hovering over nodes, makes it much more accessible to visual people.

[six7]

@mck do you think this is something that we could create in Content? Feels like we might need this for some Docs anyway, maybe we can create it agnostic to reuse (also light+dark theme agnostic)

[mck]

working on it atm