Stock toolhead adapter for Ender 3 NG (XC1)

This is a remix of ENG-XC1_b of Ender 3 NG (original file was created by RH3D). 

WARNING 1: It may not work properly. I have not finished building the Ender 3 NG at the moment of this submission. I do not have the required hardware, and have not properly tested this part.

WARNING 2: You will lose print area by using this part. I did not centralize the e-plate to avoid having to remix ENG-XC0_b, and the stock Ender 3 hot end is not centralized on the e-plate. With the stock toolhead, you will lose ~20mm of X. I intend to use it with a Hero Me Gen 5 with dual 5015 and it seems that I will lose ~30mm of X

WARNING 3: It is probably not compatible with Klicky probe. I didn't try to understand how klicky actually works, but it seems that the e plate hole that connects to the bottom wheel is in the same position of klicky. I intend to use it with bl touch instead.

The goal of this remix was to be able to use it as an adapter for the stock e-plate, but also be able to use it with RH3D's toolhead if I decide to in the future. So I just added some holes to match the e-plate, a small tab for one of the holes, and one additional hole to have a “safety screw” to prevent the toolhead from touching the Core XY timing belts.

The basic install without the safety screw requires 2 M5x8 (I used the ones that used the hold the stock mainboard) and 2 M5 self-locking nuts (also from the stock Ender 3: the ones that hold the e-plate in the wheels).

For the safety screw, you need 1 standard M3 heat insert (Hole diameter 4.1mm, insert length 5,7mm) and 1 somewhat big M3 screw. If I'm not mistaken, the stock toolhead should use a M3x14. For Hero Me, I will probably use M3x22 or M3x25