`provekit/backend/bn254/src/frontend/witness_generator`: Handling of the return value for the verifier.

[recmo]

On 2026-07-06 in 05de18e “Merge pull request #458 from worldfnd/sl/goldilocks-field-abstraction”:

Handling of the return value for the verifier.

    provekit_common::utils::serde_jsonify,
    serde::{Deserialize, Serialize},
    std::num::NonZeroU32,
};

// TODO: Handling of the return value for the verifier.

#[derive(Clone, Debug, Serialize, Deserialize)]
pub struct NoirWitnessGenerator {
    // Note: Abi uses an [internally tagged] enum format in Serde, which is not compatible
    // with some schemaless formats like Postcard.

From provekit/backend/bn254/src/frontend/witness_generator.rs:8