Replace Bezier-rs usages with Kurbo

[Keavon]

Kurbo's computational geometry is more stable, efficient, and high-quality than our Bezier-rs library which is a maintenance burden for us, and we'd like to phase it out. This issue tracks our desire to incrementally replace the many Bezier-rs usages with Kurbo equivalents wherever possible. In the end, hopefully only a few remaining functions that Kurbo doesn't support will be left, and then we can either contribute those upstream to Kurbo or move our implementations out of Bezier-rs and into Graphite/Graphene code directly.

This issue is open to anyone to work on in chunks. If you open a PR for it, say "Part of #2325" in the PR description.

[bplewis98GitHub]

I'm really new to this code base, but would love to mess around with something like this. Coming from c# development, it'll be fun

[Keavon]

@bplewis98GitHub sure, give it a shot! Replace as many as you'd like and open a PR. (I expect it will happen gradually throughout many PRs over a year or two, unless you're really productive of course!)