Function standardizeFaDateTime

standardizeFaDateTime(datetime: string): string
standardizeFaDateTime:
- Removes hidden characters (e.g., ،, \u200f).
- Unifies Persian/Arabic digits to English.
- Splits on space to separate "yyyy/mm/dd" and "hh:mm:ss".
- Zero-pads each numeric part so we end up with "yyyy/mm/dd hh:mm:ss".
Parameters
- datetime: string
  A Jalali date string from toLocaleString("fa-IR")
Returns string
A standardized string, e.g. "1402/06/03 02:07:09"
- Defined in timeAgo/helpers.ts:15