Given a timestamp (number of milliseconds since the Unix epoch), return:
"odd" if the day of the month for that timestamp is odd."even" if the day of the month for that timestamp is even.
For example, given 1769472000000, a timestamp for January 27th, 2026, return "odd" because the day number (27) is an odd number.
Note: The timestamp is in milliseconds and you should use the date in the UTC timezone, not in your local time.