Revisit auto-looting of outdoors persistent REFRs

[SteveTownsend]

Pulling up pertinent comments form Nexus:

I'm going to post this breakdown in the hope it still applies in Skyrim SE. I also need to review this in detail to resolve the CTDs, probably. https://www.afkmods.com/index.php?/topic/4250-skyrim-levels-of-persistence/ I started down this track when I noticed I could not autoloot some of the plants outdoors in The Cause. It's just never worked for some persistent REFRs, afai can tell. And that frustrates me.

CTDs sporadic in the bigger picture, but that's no consolation if your game keeps CTD-ing. I need another go round on this to handle on-demand, more like Temp REFRs, I think. The first attempt retrieved all outdoors persistent REFRs at plugin load time, cached them by CELL, and used that cache to create a list of Player CELL autoloot targets: I think that's probably too inflexible, in the light of changes to the possible persistent REFR targets during gameplay.