Act as a Principal System Architect. I have a monolithic Java application handling user management, payments, and notifications. It is suffering from slow deployment times and scalability bottlenecks. Outline a step-by-step strangler fig pattern migration strategy to microservices. Specifically address: 1) Database per service decomposition patterns, 2) Managing distributed transactions (SAGA pattern), 3) Inter-service communication (Sync vs Async), and 4) Observability and logging in the new environment. Provide a detailed architectural diagram description and a risk mitigation plan for data consistency during the transition.