Function http_request 

pub fn http_request(
    method: Method,
    url: &str,
    headers: &[(String, String)],
    body: Option<&[u8]>,
) -> Result<HttpResponse, String>

Perform a synchronous HTTP request via bun_http::AsyncHTTP::send_sync().

This function:

1. Parses the URL via bun_url::URL::parse
2. Builds request headers via HeaderBuilder
3. Initializes AsyncHTTP via init_sync()
4. Executes the request via send_sync() (blocking)
5. Extracts the response into an owned HttpResponse