`provekit/common/src/utils/sumcheck`: Figure out a way to also half the mles on folding

[recmo]

On 2025-08-29 in 2a57572 “Merge pull request #153 from worldfnd/px/refactor”:

Figure out a way to also half the mles on folding

    tracing::instrument,
};

/// Compute the sum of a vector valued function over the boolean hypercube in
/// the leading variable.
// TODO: Figure out a way to also half the mles on folding
pub fn sumcheck_fold_map_reduce<const N: usize, const M: usize>(
    mles: [&mut [FieldElement]; N],
    fold: Option<FieldElement>,
    map: impl Fn([(FieldElement, FieldElement); N]) -> [FieldElement; M] + Send + Sync + Copy,
) -> [FieldElement; M] {

From provekit/common/src/utils/sumcheck.rs:15