Resolve "What is the difference between "zeropoint" and "photometric solution"?"
Closes #63 (closed)
Assigning this to you @verdoes because this will close #63 (closed) and you might still have to say something there.
Also see the corresponding MR of the calibration plan, maybe it is easier to review that first: https://gitlab.astro-wise.org/micado/calibrationplan/-/merge_requests/29