Halo Clipping / Refactoring

[darth-cheney]

What

For a while now we've noticed several issues with Halos when used inside of complex layouts. The most important is the fact that a Halo of a part that is inside another clipped part will not be visible. Similarly, Halos inside of nested Areas might not receive click events appropriately.

Ideas

We need to think of how to deal with this. Taking the Halo out of the target Part's shadow dom is the only way to resolve some of the issues, but it will also present its own problems -- for example, movement will be more complicated and likely not as smooth.

One possibility is to only allow Halos to open in certain contexts, and to have a separate, system-wide editor pane that pops out elsewhere on the screen when a particular Part is being edited, but which has all of the functionality of the Halo too.