Function emit_while_fabric_testbench 

pub fn emit_while_fabric_testbench(
    name: &str,
    wf: &WhileFabric,
    n: usize,
    max_cycles: usize,
) -> String

A self-checking testbench for the while-CGRA: for each vector, pulse reset, clock until done, and compare result against the VM oracle from while_{name}_{in,out}.hex.