I'm not sure whether this feature request is "stats for challenges" or "a quick way to add a tag to all books in a challenge", but, I would love a way to get stat insights for challenges that I participate in. I manually made this tag (https://app.thestorygraph.com/tags/9d7e824e-e4d8-40b1-8fef-6d6b5a6a44ba) for this challenge (https://app.thestorygraph.com/reading_challenges/8d93938e-bc96-45bf-ab9a-f4bdadcbb59f) and it's been really neat to compare the stats for the books in the challenge with my overall reading, but doing that by hand for the many challenges that I am in would be arduous. I feel like it would be cool not just for challenges like that one, which is a specific list of books, but also for ones with categories like Book Riot or StoryGraph's Genre Challenge.