Add new skills for FastAPI templates, LLM evaluation, and MCP server development

Commit notes

- Introduced FastAPI templates for creating production-ready applications with async patterns and dependency injection. - Added LLM evaluation strategies for comprehensive performance measurement of LLM applications, including automated metrics and human feedback. - Created a guide for developing high-quality MCP servers, detailing best practices, implementation patterns, and evaluation guidelines. - Included reference files for evaluation and best practices to support MCP server development.