Build an Agora Conversational AI Backend with Express

This Express server handles real-time voice conversations with AI agents using Agora's Conversational AI Engine. It provides a basic structure for connecting to an existing LLM workflow and enables users to invite, remove, and manage AI agents within the conversation. The server includes validation middleware to ensure proper request handling and uses environment variables to configure various settings such as TTS vendors, LLM configurations, and Agora credentials. The development server is set up using Nodemon for automatic restarts when files change, allowing developers to quickly test and iterate on their API endpoints.