* Disable ZK in large_config
Speeds up the tests from ~6m to ~1m (debug mode). `large_config` is crate-private so I don't think we need to worry about real users forgetting ZK, and I don't think ZK seems important in these tests, though we should probably have ZK enabled for a couple tests.
A couple tests need ZK or they fail; I added a TODO to look later.
This led to a few other changes:
- Fixed a bug where `trim` could truncate the final poly to a non-power-of-two length. This was improbable when ZK is on due to randomization.
- Gave a few methods access to the whole `CircuitConfig` vs `FriConfig` -- sort of necessary for the above fix, and I don't think there's much downside.
- Remove `cap_height` from `FriConfig` -- didn't really need it any more after giving more methods access to `CircuitConfig`, and having a single copy of the param feels cleaner/safer to me.
* PR feedback
It's just a wrapper around `Target`, which signifies that the wrapped `Target` has already been range checked. Should make it easier to audit code that expects bools.
This is detecting the case where we multiply something by 1 and add 0. In that case we can just return the thing being multiplied by 1. We were using the wrong constant to detect this.
Reduces the cost of `compute_evaluation` from 8 to 6 gates.
We previously checked for special cases, like arithmetic on constant Targets, in `arithmetic`. We can handle those cases without actually adding an `ArithmeticGate`.
Now that `arithmetic` just calls `arithmetic_extension`, it makes more sense to check for special cases in the latter method, so it applies to both base and extension field arithmetic.
Reduces gate count from 16149 to 15689.
