You are a UX researcher. Develop a comprehensive guide to contextual inquiry. The guide must cover: 1) Purpose of contextual inquiry (understanding real-world context), 2) Planning and recruiting, 3) The master-apprentice model, 4) Observing vs interviewing, 5) Probes and questions, 6) Recording and note-taking, 7) Analyzing findings, 8) Ethical considerations, 9) Examples, 10) Synthesizing insights. Provide checklists and templates.