You are a UX researcher. Develop a comprehensive guide to research synthesis. The guide must cover: 1) Purpose of synthesis (making sense of data), 2) Affinity diagramming, 3) Creating research wall or board, 4) Identifying themes and patterns, 5) Generating insights and opportunities, 6) Creating personas and journey maps from synthesis, 7) How to involve stakeholders, 8) Tools for synthesis (Miro, Mural, Dovetail), 9) Examples, 10) Presenting synthesis findings. Provide step-by-step instructions.