Point light API

[marceline-cramer]

• Define PointLight and supporting handles
• Add point light Renderer API
• Shade point lights in opaque pass
• Add point lights to cube example

Checklist

• CI Checked:
  • cargo fmt has been ran
  • cargo clippy reports no issues
  • cargo test succeeds
  • cargo rend3-doc has no warnings
  • cargo deny check issues have been fixed or added to deny.toml
• Manually Checked:
  • relevant examples/test cases run
  • changes added to changelog
    • Add credit to yourself for each change: Added new functionality @githubname.

Related Issues

Description

Adds a rudimentary point light API. No clusters and no shadow mapping yet.

[cwfitzgerald]

This is absolutely fabulous code!

I have some small changes, but by and large the code fits in extremely well and looks great

[cwfitzgerald]

Let's goooooo!