Add an inference option to ignore the recursion hardlimit

[Keno]

We currently very aggressively limit recursion if we came from a union split. The reason for this choice is to avoid accidental exponential inference times from excessive exploration of the call graph. Unfortunately, certain packages like Diffractor really like triggering the recursion heuristic at the moment, causing any unions to immediately cause imprecise inference. In the fullness of time, we should improve the recursion heuristic to do better in this case, but for the time being, add an inference option that simply lets it ignore the hardlimit recursion case and proceed anyway.

[vtjnash]

SGTM. Though I would suggest that packages should never blindly opt all users into this, but only applications might be given the option to specifically bypass it for specific kernels.