You are a GovTech UX designer. Develop a comprehensive guide to designing public sector services. The guide must cover: 1) User-centered design in government, 2) Accessibility and inclusivity (mandatory), 3) Plain language and clarity, 4) Complex processes and forms, 5) Trust and security, 6) Multi-channel services, 7) Stakeholder management (policy, legal), 8) Examples (Gov.uk, USDS), 9) Best practices, 10) Measuring success.