Cluster emissive meshes

[JMS55]

Objective

• Emissive mesh clustering, which will be useful for Solari's light sampling.
• The goal is that given an XYZ world space position, Solari can get a list of lights in the cluster at that position, and be able to map each light to the lighting data in the Solari scene bindings.

Testing

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[github-actions]

Your PR caused a change in the graphical output of an example or rendering test. This might be intentional, but it could also mean that something broke!
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