BLTouch 40mm Fan Mount for Hydra Fan Duct

This is a remix of Michael's elegant BLTouch mount for 40mm fan housings.

This is made to specifically work with BoothyBoothy's amazing Hydra Fan Duct on an Ender 3 using a stock hot end.

This remix has lengthened the part so the BLTouch sits at a distance from the bed that works well with the Hydra setup.

On my Ender 3 Pro with Hydra fan duct and BL Touch Smart v2.0 setup, the Marlin firmware offsets are:

X_PROBE_OFFSET_FROM_EXTRUDER: 0
Y_PROBE_OFFSET_FROM_EXTRUDER: -36
Z_PROBE_OFFSET_FROM_EXTRUDER: -1.2

*** UPDATE ***
After some close examination, and comments from users, I realized that the original mount had the BLTouch angled slightly outwards. So I've cantered the BLTouch by 4 degrees to ensure that it's orientated vertically.

There are also new variations for each BL Touch Smart version (as of this writing) so that the probe offset from the nozzle is within specs. The v3.0 is also correct for v3.1 BL Touch.