For the "shelter" there is already the tag "winter_room" and "capacity:winter_room".
The capacity of the hut can be given simply as "capacity".

Tagging chief/guardian/operator at the same time seems a bit difficult.  There is "contact:person" that might be used for the person you get into contact with in case of (remote) questions.

non_catered would be simply "kitchen=yes", not a cuisine tag.

half_board can be tagged as "breakfast" and "dinner".

