JetFramework/Jet ? reverse-engineered prompt

Build me a small Python web framework called Jet that feels simple to use and easy for beginners to read.

I want route handlers to just be normal Python functions, with pages that can render HTML templates, plus basic request and response objects. Please include a built in development server with a nice startup message, request logging, and auto reload, and make the jet command able to run the app from the terminal.

It should also serve static files, handle uploads, and automatically expose /docs and /openapi.json with a simple API docs page. Keep the code clean and lightweight, with the app logic separated from configuration, and make the example app work out of the box.

If anything is unclear, check current docs online first, then implement it in a way that feels polished and easy to extend later.