Dispose of corpse prevents respawning after load

Dispose of corpse and SetDelete 1 call World::deleteObject which sets the ref's count to 0. We don't save stats for actors with a count <= 0: https://gitlab.com/OpenMW/openmw/-/blob/master/apps/openmw/mwclass/creature.cpp#L799 https://gitlab.com/OpenMW/openmw/-/blob/master/apps/openmw/mwclass/npc.cpp#L1352 This is correct for SetDeleted actors, but for disposed corpses it means we don't save that the death animation has finished playing. This causes respawning actors to never respawn. (Which, again, is correct for SetDeleted actors.) Note that SetDeleted actors that died before being deleted will respawn in Morrowind.exe.

As reported on Discord by ted https://discord.com/channels/260439894298460160/260443579908882434/1003828031518945321 with a video in which the issue is encountered when killing an ordinator wander and reloading a save after disposal but before it should've respawned https://discord.com/channels/260439894298460160/260443579908882434/1003828041270698014

Seems to have been introduced in 0.47: https://github.com/OpenMW/openmw/pull/2715