Function prove_stark 

pub fn prove_stark<SC>(
    config: &SC,
    trace: &RowMajorMatrix<Felt>,
    public_values: &[Felt],
    var_len_public_inputs: VarLenPublicInputs<'_, Felt>,
    aux_builder: &AuxTraceBuilders,
) -> Result<Vec<u8>, ExecutionError>
where
    SC: StarkConfig<Felt, QuadFelt>,
    <SC::Lmcs as Lmcs>::Commitment: Serialize,

Generates a STARK proof for the given trace and public values.

Pre-seeds the challenger with public_values, then delegates to the lifted prover. Returns the serialized proof bytes.