Function run_modl_qsm 

fn run_modl_qsm(
    local_field_ppm: &[f64],
    mask: &[u8],
    grid: &Grid,
    bdir: (f64, f64, f64),
    tile: Option<(usize, usize)>,
    progress: &mut dyn FnMut(usize, usize),
) -> Result<Vec<f64>, PipelineError>

Source the MoDL-QSM prior-CNN weights and run inference (requires the onnx feature). Output is the STI χ33 component.