They'd probably be your NPC's. The summoning/animation doesn't take very long, but that doesn't have to mean the duration of the spell is as short. Actually I'm not quite sure how that would be treated, is it a duration 1-2 for the summoning or is that also the lifetime of the summoned creature? Would probably make sense to make a spell summoned creature live as long as the duration, while a ritual summoning would last longer or even be permanent.
Yes. For creation spells, the duration would be the length of time that the thing/being lasts.
