Capstone: The Inference Bill

1. The Exercise

This capstone is deliberately narrow, and deliberately quantitative. The skill it teaches is sizing and pricing an inference layer out loud, in an interview, under real time pressure. That is exactly the skill this whole module exists to build. Here is the question:

"We're adding an AI assistant to our project-management SaaS (think Jira/Asana scale): 5 million daily active users. The assistant answers questions about the user's projects, drafts updates, and summarizes threads. Product wants it on every screen. You own the inference layer: design it and tell us what it c