feat: callback events on pill

To do:

• Add callback events when pill and passed-in icon are clicked
• Remake pill's story with input options instead of listing all variants

Design review:

• This adds "functionality" to the tags above a list view. Design wise, it's not a lot of new stuff. Just check the clicking behavior of the tags.
• Tag cloud with category pills
• Pill story (please also click on pill and its icon to verify event callbacks)