Timeline UX fixes (chronological sort, 12/24h format, default-date-today)

I've created a booking, of type "Wedding", I've entered the date, start time, end time, and location of the booking; the booking timeline should already have golden hour, sunset, etc., pre-filled for me, based on easy math / lookups. It should also have a default preset list of items for me to edit / delete, like ceremony, reception, etc.

Big the biggest annoyance of all, is when I create a new timeline item, the default date / time is the current date / time, not the date of the booking, or a time after the previous timeline item.