Implement changes to assumptions and the resolve program

[nategraf]

As the main changes to RISC Zero for the generalized composition design, the assumptions encoding, and how it is handled in the resolve recursion program needs to be changed to allow specifying a distinct control root.

[linear[bot]]

ZKVM-416 Implement changes to assumptions and the resolve program

[flaub]

I think this is done, but if that's not right, please re-open