Operators with local sparsity > global sparsity

[gdalle]

• min and max: only one of the argument matters at any given point => min(x, bigy) = x
• mod and rem: depending on their relative sizes, one of the arguments may not matter => mod(x, bigy) = x
• same with a subset of https://docs.julialang.org/en/v1.10/manual/mathematical-operations/#Division-functions

[gdalle]

Once we have primal values, we will also need to add new operators, mostly those that work with Bool:

• isequal, isless, isfinite, isinf, isnan
• possibly their friends ==, <, <= and co (check the fallback structure for those again)

[gdalle]

Closed in favor of #56