I would not apologize, I would try to develop a sense of humor about your worry-wart of a mother and just not take her so "seriously".

When she says something obvious, just flash her a smile and occasionally thank her. If you "agree" with her, she has no way of continuing/being unhappy with you or your attitude.

When she says something, treat it like a checklist and mentally congratulate yourself that you have already done/thought that (and that she taught/trained you so well!). Believe me, when she is gone, you will wish she were still there bugging you and being "Mom".