WebGPU support

[EricLBuehler]

@KimHenrikOtte I saw your work on your Candle fork, and some benchmarks which you released that seem impressive. I'd be interested in including these changes here where we could feature them through mistral.rs, would perhaps you be interested in working on an integration?

[Unrealiter]

To ensure we're on the same page:
mistral.rs is a library you developed, which is based on candle.
For this library, you used a custom fork of candle, correct?

Does this mean you couldn’t simply use something like the following in your Cargo.toml?

candle-core = { git = "https://github.com/KimHenrikOtte/candle.git", version = "0.8.1", features = "wgpu", branch = "wgpu_cleanup" }

Unfortunately, I don’t have the time to investigate this repository further at the moment.