Canonicalization tests and mul_canon

[Transurgeon]

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[Transurgeon]

just writing down some thoughts from the tests:

the paper by smith says we should introduce new variables for both the numerator and denominator of a division operator.

Maybe we could try doing that as well.

Another point is the second sentence of the image above : "We also need to replace the entire
expression by a new variable defined in terms of a linear fractional term". I am wondering if this means we should just create a new variable and set its value to w_j.value/w_{j+1}.value. The alternative would be to create an equality constraint with w_{j+2} == w_j.value/w_{j+1}.value. Basically, I am wondering if we should differ between equality constraints and a new variable "defined in terms of a linear fractional term". However, one thing is sure, we should output a new variable for the output of the div operator.