Recently, I've been working with a friend to build a multi-author blog website using WordPress. We need to display the most active authors who have published the most articles. The WordPress function `wp_list_authors` can list all authors along with their article counts, but it doesn't allow sorting by the number of articles or limit the number of authors displayed. So, let's take matters into our own hands.
The required extended functionalities are:
1. Display the authors with the most articles, sorted by the number of articles;
2. Customize the number of authors to be displayed.