Various Rust-related experiments and benchmarks. Run cargo android for building for aarch64.

TODO:

• Add various versions of v3 (with workgroup memory)

• Add various optimizations from https://cnugteren.github.io/tutorial/pages/page4.html

• Write a bugreport for threadgroup sizes in wgpu+metal

• Benchmark on Qualcomm, including unchecked/restrict bounds vs robustness

• Write a feature-request for unchecked/restrict bounds

• Add aarch64 to basic_simd

• Add basic_gpu_compute

• Bench music.ogg/music.mp3/music.flac against each other.