Every second, once you've moved X amount, you query pocketbase for props near your X,Y location. It returns all those props.
Any prop already in the scene (which is in your radius) is ignored, any new props are spawned in a belated order (so you don't load 100+ cloud assets at once, at an attempt to smooth out fps spikes). Any outdated props are removed.
Persisted props are a dumbed down version without physics or intractability (Basically static).