allow to specify min_group_size in graphs that include grouping (e.g. using 'color', 'facet_row/col' etc.)

when using 'grouped' plots, we'd often like to see trends/differentations between separate groups.
however, it is common that some of the groups are very 'small', thus the data shown for them is confusing (and sometunes also distorts the rest of the plot, because the range can be very large).

i think allowing specification of min_group_size (Optional[int]) can be very beneficial, mitigating this issue, and eliminating the need of boilerplate code from the user side.

thank you for all your great work!

首先跟踪支持 color、facet_row 和 facet_col 的分组绘图路径，然后检查其现有测试和分组行为。定义 Optional[int] min_group_size 应如何应用于这些分组选项，包括无效值或省略值。完成的标准是：小组能够被一致地排除，而无需用户自行筛选，并且为受支持的分组场景提供覆盖。