Feat: Adds rust config options to detect threading support in oxide

[jlukic]

This modifies Oxide to use helpers for parallel processing that allow Oxide to compile to unknown-unknown.

This lets Oxide work in the browser without dealing with the rabbit hole of permissions around using SharedArrayBuffer which include custom HTTP header requirements like Cross-Origin-Embedder-Policy and Cross-Origin-Opener-Policy

This is used in tailwindcss-iso and you can see the wasm in use in Semantic Playground here

#11610

[thecrypticace]

I'm planning on taking a look at this soon btw. One thing I definitely want to figure out is a way to unify the Node + WASM APIs (so like no separate WasmChangedContent or WasmScanner types and what not) so there's less duplication if I can.

[thecrypticace]

Reminder for me to investigate soon: NAPI-RS v3 is out now. There's a chance things can be simplified with that re: WASM

[jlukic]

Really good point it seems like that would make everything a lot simpler

https://napi.rs/blog/announce-v3

WebAssembly is the biggest update this time. In V3, you can compile your project into WebAssembly with almost no code changes. If the compilation target is wasm32-wasip1-threads or higher, you can directly run code that uses Rust features like std::thread and tokio in the browser without any additional modifications.