Bag-and-Whisker Plot // Implementation of the Bag-and-Whisker Plot for bivariate data. Provides a single user-facing function bag_whisker() that wraps the computation and plotting helpers in this package. For more details, please refer to the paper "The Bag-and-Whisker Plot: A New Bagplot for Bivariate Data" by Qin, Gang, Tong and Cui (2025) doi:10.48550/arXiv.2512.06314.