GroupingColumnsConfig
Since v1.9.0
Grouping-columns config widened to accept Vue render functions for
groupHeaderRenderer and the per-group renderer inside columnGroups.
type GroupingColumnsConfig = Omit<CoreGroupingColumnsConfig, "groupHeaderRenderer" | "columnGroups"> & { columnGroups?: ColumnGroupDefinition[]; groupHeaderRenderer?: CoreGroupingColumnsConfig["groupHeaderRenderer"] | (params: GroupHeaderRenderParams) => VNode }