Add whenEntityLoads overloads for non-Pylon entities #503
Description
This would be very useful to have (I've run into a scenario where it would be very useful, and I think we will need it in the future for similar scenarios).
Potential implementation is effectively the same as the current implementation for Pylon entities, with a few tweaks. Potentially using the exact same fields but I'm not sure.
Feels a bit weird to put this in EntityStorage but not sure where else it should go, so that's probably fine.