continue drafting API for cardano fuzzers.
The strategy is to map every type from stdlib to its own "general fuzzer" taking no argument and yielding a fully arbitrary value; or, have `_with` fine-grained fuzzers for each of the type's variants that take additional fuzzers as arguments. We're also thinking that having those fuzzers check for well-formness of data (e.g. policy id is 28 bytes) is a good idea, so that what comes out of those is somewhat well-formed data and phase-1 validations down the line are simplified.