You are a UX designer and agile expert. Develop a comprehensive guide to user story mapping. The guide must cover: 1) Purpose of story mapping (backlog organization, user-centered), 2) Creating a story map (backbone, walking skeleton, tasks), 3) Facilitating story mapping workshops, 4) Prioritization techniques, 5) Release planning with story maps, 6) Examples, 7) Tools for story mapping, 8) Integrating with agile development. Provide templates and instructions.