Multiplication modulaire sur le cercle-OLD

Initialy, i found this idea from Michaël LAUNAY on Youtube (https://www.geogebra.org/m/MXbWpzS6). Freely inspired from Steve PHELPS (https://www.geogebra.org/m/dqKkQEv7) and Johan MATHIEU (https://www.geogebra.org/m/MXbWpzS6), and some others also, right here. Thanks to all of them for this beauty !