In addition to the many nice examples others have mentioned, I would like to point to one book of which I am currently in the middle: Becky Chambers's "The long way to a small, angry planet". This book is delightfully conflict-free so far, and it's hard to think it's not intentional; indeed, one of the (non-human) characters even lampshades it during a gaming session by referencing the way that human games seem always to be built around conflict and competition.