[TASK] Mixer ProverSetup

[lazovicff]

Instead of macros, we should have a ProverSetup struct, like so:

pub struct MixerProverSetup<
	F: PrimeField,
	H: CRHTrait,
	HG: CRHGadget<H, F>,
	LHGT: CRHGadget<P::LeafH, F>,
	HGT: CRHGadget<P::H, F>,
	P: Config,
	const K: usize,
> {
	h3_params: H::Parameters,
	h5_params: H::Parameters,
	leaf_params: <P::LeafH as CRHTrait>::Parameters,
	inner_params: <P::H as CRHTrait>::Parameters,
};

impl MixerProverSetup {
	fn setup_arbitrary_data(...);
	fn setup_leaf(...);
	fn setup_tree_and_root_set(...);
	fn setup_circuit(...) -> (
		MixerCircuit,
		Vec<F> // Public inputs
	);
	fn setup_circuit_with_random_inputs(...);
	fn setup_circuit_with_raw_inputs(...);
	fn setup_proving_and_verifying_key(...);
	fn prove(...);
	fn verify(...); // For testing
}

Inside tests should be used like so:

let params3 = setup_hash_params();
let params5 = setup_hash_params();
let prover_setup = ProverSetup::new(params3, params5, ...);

let relayer = 1;
let recipient = 2;
let fee = 300;
let refund = 200;

let (circuit, public_inputs) = prover_setup.setup_circuit_with_raw_inputs(relayer, recipient, fee, refund);

let proof = prover_setup.prove(circuit);

let res = prover_setup.verify(public_inputs, proof); // Check if proof is valid