Fixed arc reactor crystal

Modified the "crystal" part to actual fit as intended.

As many others noted in the comments on the original, the "crystal" model has no spacing between it and the top part that slides over it, so the crystal requires a TON of sanding to fit properly.

This remix just adds 1mm of space anywhere the crystal would contact the top part, so now they slide together easily but still fit snugly.

The Fusion 360 file is included in case you need to tweak that spacing. But be warned that Fusion 360 struggles to perform boolean operations on a mesh that complex, so it either takes several minutes to process or just crashes when you make a change.