Add shadow to connections that don't connect to components

[AdRiley]

Objective is to make it clear when connections are passing under a component not connected to it.

The idea is to make the component cast shadows onto the connections that are not connected.

Ideally something like this https://shadows.brumm.af/ for the shadow

Need to check performance

[farmaazon]

Refinement notes:

• Definitely not easy, especially to make it with good performance.