curious behavior of "intersect"

The two answers should be the same:
```m2

i1 : R = QQ[x,y]

o1 = R

o1 : PolynomialRing

i2 : intersect (monomialIdeal (x*y^2), ideal (x^2*y))

2 2
o2 = monomialIdeal(x y )

o2 : MonomialIdeal of R

i3 : intersect (ideal (x^2*y), monomialIdeal (x*y^2))

2 2
o3 = ideal(x y )

o3 : Ideal of R
```

Start by reproducing the two intersect calls in the Macaulay2 interpreter using the example over QQ[x,y]. Trace the intersect entry point and its handling of Ideal versus MonomialIdeal arguments; done means both argument orders produce the same result and compatible type.

Written by the indexing model from the issue text.