Allow specifying a different instance count for editor

[tavurth]

My Mackbook is not so great in terms of GPU 😅

It can handle a lot of objects while testing a game, but I'd rather not thrash away at the GPU while I'm editing the map.

Perhaps having an option to decimate the mesh instance while in the editor would solve this? That way I can test and everything looks great, but I don't waste my battery life or have to listen to my fans while I'm editing the map.

[HungryProton]

That's probably something easy to add, there's already an option called Preview Count to lower the instance count while editing the path, but once you're done it displays the final result. I could add a checkbox to make the preview permanent.