SmartAlu new X carriage with radial fan duct(s)

I redesigned the X carriage to improve the tightness of GT2 belts grip and avoid having metal bolts screwed into plastic (here, everythings holds with metal nuts inserted in cavities reserved in the printed parts), move the Zinduction sensor on the back part to make room for fanducts, and have the possibility to install one or even two radial fan with complete fanducts to perfectly cool the printing.
It's provided with a new X axis endstop and two heights for the radial fanduct bottom part, dep