One time, I stored my baggage at CDG Airport in Paris for 1 day. I organised my flights so that I had a full day off between connecting flights. I trained it into Paris for lunch, a walk, and a coffee. This temp storage cost me a lot of money. Don't do it this way.
Presumably, you'll be away from Paris for about a month. My guess is it will cost you a lot of money if you use the hotel for storage. Try to find a user-friendly, less mainstream solution. Try a large train station - there are (I think) 4 biggies in Paris but I'm not sure about longterm storage there. Cumbersome but less financially painful, is my guess - you might be able to rent a locker by the month.
It might be too inconvenient for you to double back to your Camino start point on your way to Paris from (?) Santiago. Wokabout_Meri has offered some solutions. I'd contact her.