Function laplacian_weights_ilsqr 

fn laplacian_weights_ilsqr(
    f: &[f64],
    mask: &[u8],
    nx: usize,
    ny: usize,
    nz: usize,
    vsx: f64,
    vsy: f64,
    vsz: f64,
    pmin: f64,
    pmax: f64,
) -> Vec<f64>

Laplacian weights for iLSQR (Equation 7)

Weights based on Laplacian magnitude with percentile-based thresholding.