[Mainline Fix] Weather effects go through custom entities

[Goldenfield192]

This PR makes rain and snow particles no longer go into entities (currently only IR's stocks)

To be discussed before merging:

• Should we make it a togglable feature in CustomEntity?

[cam72cam]

What's the performance impact of this change?

[Goldenfield192]

What's the performance impact of this change?

Ideally the more entity there are around plyaer, the more calculation ti does
However Minecraft's rain is only particles rendered around the player with the radius of 10 (In the worst case 4 chunks), I think performance impact would be seamless
Exact result needs profiling (will do as soon as I can)

[Goldenfield192]

What's the performance impact of this change?

Update with profiler result:

With no entity nearby the result remains the same as vanilla rains, but with 80 model stocks within raining range it caused 420x slower to target method

Need in-depth optimization