The Inventory domain is meant for all characters, i.e. those than can have
an "inventory".
It's a non physical domain, which means that entities contained in it won't
be affected by any physical constraints, or have physics applied to them.
Visibility for outside entities are by default forbidden unless an entity is
outfitted or wielded.
The idea is that other playes shouldn't see what's in the inventory of another
player, unless things are outfitted or wielded.
