[bug] Using Chinese characters in the options parameter of the invoke method causes the type returned by request.body() to be not Raw.

[SRutile]

Describe the bug

I encountered an issue when using the writeFile method. If Chinese characters are present in the options parameter of the invoke method, it causes the type returned by request.body() to be not Raw.

Reproduction

#[tauri::command]
async fn test(
    request: tauri::ipc::Request<'_>,
) -> Result<(), String> {
    println!("{:?}", request.body());
    println!("{:?}", request.headers().get("path"));

    if let tauri::ipc::InvokeBody::Raw(data) = request.body() {
        println!("{:?}", data);
    } else {
        println!("failed");
    }
    
    Ok(())
}

const data = new TextEncoder().encode("H");
invoke("test", data, {
    headers: {
        path: "a测试"
    }
})

Json(Array [Number(72)])
Some("aa\xe6\xb5\x8b\xe8\xaf\x95")
failed

Expected behavior

Make request.body() return the type as Raw.

Full tauri info output

[✔] Environment
    - OS: Windows 10.0.19044 X64
    ✔ WebView2: 128.0.2739.42
    ✔ MSVC: Visual Studio Community 2022
    ✔ rustc: 1.82.0-nightly (100fde524 2024-08-28)
    ✔ cargo: 1.82.0-nightly (8f40fc59f 2024-08-21)
    ✔ rustup: 1.27.1 (54dd3d00f 2024-04-24)
    ✔ Rust toolchain: nightly-x86_64-pc-windows-msvc (default)
    - node: 20.15.0
    - pnpm: 9.4.0
    - npm: 10.8.1
    - bun: 1.1.17

[-] Packages
    - tauri [RUST]: 2.0.0-rc.7
    - tauri-build [RUST]: 2.0.0-rc.7
    - wry [RUST]: 0.42.0
    - tao [RUST]: 0.29.1
    - tauri-cli [RUST]: 2.0.0-rc.5
    - @tauri-apps/api [NPM]: 2.0.0-rc.3
    - @tauri-apps/cli [NPM]: 2.0.0-rc.7

[-] App
    - build-type: bundle
    - CSP: unset
    - frontendDist: ../dist
    - devUrl: http://localhost:1420/
    - framework: Vue.js
    - bundler: Vite

Stack trace

No response

Additional context

No response

[amrbashir]

This is just how headers work, only ISO-8859-1 strings is accepted as valid header. To workaround this, you can use encodeURIComponent and then use percent_encoding crate on Rust side to decode the value.