AI Knowledge Assistant Integration for Existing MERN SaaS Dashboard

We have an existing MERN-based SaaS platform with user authentication, an admin dashboard, and core business functionality already in place. We are looking for a Full-Stack MERN developer to integrate an AI-powered Knowledge Assistant as a new feature within our application. The goal is to allow administrators to upload company documentation (PDF, DOCX, TXT), which users can then query through a conversational AI interface. The assistant should provide accurate, context-aware responses based only on the uploaded documentation. Scope of Work - Add a new Knowledge Assistant module to the existing dashboard - Implement document upload functionality (PDF, DOCX, TXT) - Process uploaded documents for AI retrieval - Integrate OpenAI API for question answering - Build a conversational chat interface - Display document source references where applicable - Store conversation history - Allow administrators to replace or delete uploaded documents - Implement loading states and error handling - Ensure responsive, production-quality UI