Function toggle_sorting_handler_tanstack 

pub fn toggle_sorting_handler_tanstack<TData>(
    sorting: &mut Vec<SortSpec>,
    column: &ColumnDef<TData>,
    options: TableOptions,
    event_multi: bool,
    auto_sort_dir_desc: bool,
)

TanStack-aligned sorting handler state transition (UI handler semantics).

This mirrors column.getToggleSortingHandler() which first checks getCanSort() (and thus respects enableSorting) and uses getCanMultiSort() + isMultiSortEvent to decide whether a multi-sort toggle is active.