`Date::day_of_week` is a bad name
This method returns a Weekday, i.e. Monday/Tuesday. This is a different concept from "day of week", where Monday can be day 1 or day 2.
We should rename to Date::weekday and deprecate the current method.
I think the name is because CLDR calls it "day of week", similar to "day of month" and "day of year"
https://unicode.org/reports/tr35/tr35-dates.html#dfst-day
But since the type it returns is called Weekday we could call the method weekday too. 🤷
CLDR calls this "Day of week name", which is not the same as the other field it calls "local day of week number/name".
Seems like this is at least partially resolved. Robert to determine if this is done and close if so.