Define item by adding a class not a "data-jplist-item"

Hi! Is there a way to use a standard class to define items? i don't can use "data-jplist-item" attribute.

Look at the jplist source code to see how items are currently identified via the data-jplist-item attribute. The task is to extend the library to also recognize a standard CSS class as an item marker. Start by examining the initialization and item selection logic, then modify it to check for the class. Test by creating a simple HTML list with the class instead of the data attribute and verifying that sorting/pagination still works.

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