Advanced AI Prompt for Low-Level Design (LLD) Class and Sequence Documentation

Act as a Lead Software Engineer and Systems Modeler. Translating from a provided HLD, generate a hyper-granular Low-Level Design (LLD) specification specifically for the [MODULE_NAME] subsystem. Based on the provided raw [CLASS_STUBS], you must define the absolute internal logic and architecture of every single class. This includes explicitly typing all private/public attributes, defining the exact method signatures, and specifying the expected return data types. Provide a heavy technical justification for the implementation of specific [DESIGN_PATTERNS] (e.g., enforcing a Singleton for the DB connection pool, or an Observer pattern for event handling). Output the exact Mermaid.js syntax to render a highly complex UML Class Diagram. This output is designed to be ingested directly by a coding LLM to immediately begin writing the actual production codebase.