Suggestion: Multithreading Performance Comparison

[cyy-2024]

I believe adding a multithreading performance comparison to the benchmark would be beneficial. It could provide valuable insights into how different PDF libraries handle concurrent tasks, especially in a multithreaded environment, helping users choose the right tool for high-performance requirements. I hope this suggestion could bring some inspiration to the project. Thank you for considering it! As someone who is just starting out, I'm eager to learn more from this experience.