Move to hanabi for particles

[eira-fransham]

Motivation

Currently all particles are handled on the CPU. Rendering them is batched, but we can do much better.

Proposal

Hanabi is a GPU compute-based particle system which should allow us to have far less hand-rolled behaviour and far better performance.

Issues

All particles are still stored in a centralised way, and so we need to start splitting the centralised types into components before we can do anything. Additionally, Quake has particles that can spawn on mesh vertices, and handling that will take a fair bit of complexity.