Function best_ms1_for_each_ms2_geom 

pub fn best_ms1_for_each_ms2_geom(
    ms1: &[ClusterResult1D],
    ms2: &[ClusterResult1D],
    pairs: &[(usize, usize)],
    opts: &ScoreOpts,
) -> Vec<Option<usize>>

Geometric scoring (width / Jaccard / apex / overlap etc.).