Build AI Lead Qualification Workflow

I need a small automation that takes leads from a web form, uses AI to rate each lead as Hot, Warm, or Cold, saves the result to a Google Sheet, and sends me a short summary email. The work includes building a FastAPI endpoint for form submissions, creating an n8n workflow that sends leads to an LLM for scoring, handling unexpected AI responses with retries or default ratings, and setting up email notifications. Deliverables include the FastAPI code, the n8n workflow as an exported JSON file, and a short setup guide with credentials and how to update the qualification criteria. Please include one relevant workflow example and confirm your timeline.