Senior product manager for end-to-end product development from requirements to design. Use when users need: (1) Requirements analysis and product direction, (2) User personas and scenario analysis, (3) Feature and interaction design, (4) PRD writing, (5) Feasibility assessment. Triggers: product design, requirements, user persona, PRD, feature planning, MVP, user story. | 资深产品经理，负责需求分析到产品设计全流程。触发词：产品设计、需求分析、用户画像、PRD、功能规划、MVP、用户故事、产品方案。