Project: datamanagement
Issue DM-1987: Redesign/Refactor WCS and Coord
%50 KSK, %50 RO Currently WCS is mutable and Coord objects are heavyweight. Refactor WCS to be immutable and make Coord less heavyweight. Include lists of Coord objects. It's possible astropy could inform in that area. Also, remove TanWcs in favor of TanSipWcs since TanWcs can have SIP terms.
Story points: 40