Add component to control entity view distance.

[rj00a]

Describe the problem related to your feature request.

The view distance of entities and the view distance of chunks are one and the same in Valence. However, the client will stop rendering entities past a certain distance, so it's a waste to keep sending packets for those entities.

What solution would you like?

Split the existing ViewDistance component in two: ChunkViewDistance and EntityViewDistance. ChunkViewDistance is still in control of the view distance "fog" effect and is the "real" view distance understood by the protocol.

Internally, the real value of EntityViewDistance is clamped such that entity_view_distance <= chunk_view_distance since entities don't render past the chunk view distance.

What alternative(s) have you considered?

To reduce complexity, we could have the entity view distance fixed to whatever that maximum render distance for entities is.