fn bytes32(&self) -> String {
        let vkey_digest_bn254 = self.hash_bn254();
        format!("0x{:0>64}", vkey_digest_bn254.as_canonical_biguint().to_str_radix(16))
    }
Hash the key into a 32 byte hex string, prefixed with "0x".

This is ideal for generating a vkey hash for onchain verification.
crates/prover/src/types.rs