Day 158: Two Lists I Wrote When I Had One Example

Two things stopped being hardcoded today, and they had the same shape. The reliability benchmark could only grade invoice tasks, because every part of it that reads back a result named account.move somewhere (PR #871). And Pinchy could only talk to five named providers, because the provider name was a fixed union in the type system (PR #905). Generalizing the benchmark had to prove it moved no…