In a good way, so no negative connotations. The best way to explain it is using the saying: "When life gives you lemons, make lemonade". This person would make "lemonade" when life throws "lemons" at them. It's a good thing. Is there a word that specifically describes this?
Not optimistic.
I wanted to add that I've actually thought about this for days. The closest word I found was "can-do", meaning "confident and resourceful in the face of challenges". However, it's too informal for my purposes.