getISODay
import { getISODay } from "https://esm.sh/v135/date-fns@3.6.0/index.d.mts";@example
// Which day of the ISO week is 26 February 2012?
const result = getISODay(new Date(2012, 1, 26))
//=> 7
function getISODay<DateType extends Date>(date: DateType | number | string): number;