ChauBoxplot - Chauvenet-Type Boxplot

Provides a modified boxplot with a new fence coefficient determined by Lin et al. (2025). The traditional fence coefficient k=1.5 in Tukey's boxplot is replaced by a coefficient based on Chauvenet's criterion, as described in their formula (9). The new boxplot can be implemented in 'base R' with function chau_boxplot(), and in 'ggplot2' with function geom_chau_boxplot().