Function curl_text_with_args_headers 

pub fn curl_text_with_args_headers(
    url: &str,
    extra_args: &[&str],
) -> Result<CurlResponse, Box<dyn Error + Send + Sync>>

What: Fetch plain text from a URL using curl with custom arguments, including headers.

Inputs:

• url: URL to request
• extra_args: Additional curl arguments (e.g., ["--max-time", "10"])

Output:

• Ok(CurlResponse) with response body, status code, and parsed headers; Err if curl or UTF-8 decoding fails

Errors

• Returns Err when curl command execution fails (I/O error or curl not found)
• Returns Err when curl exits with non-zero status (network errors, HTTP errors, timeouts)
• Returns Err when response body cannot be decoded as UTF-8

Details:

• Executes curl with -i flag to include headers in output.
• Uses -w "\n%{http_code}\n" to get HTTP status code at the end.
• Parses Retry-After header from response headers.
• Separates headers from body in the response.