整洁架构完全指南：构建可维护、可测试的软件系统

This is a comprehensive guide to Clean Architecture, a software design principle proposed by Robert C. Martin (Uncle Bob), which organizes software into four layers: Domain, Application, Presentation, and Infrastructure. The core rule is that dependencies must only point inward—outer layers depend on inner layers, never the reverse—achieved through Dependency Inversion. Each layer is illustrated with Python code examples including Order entities, use cases, FastAPI controllers, and SQLAlchemy repositories.