chatchat-space/Langchain-Chatchat ? reverse-engineered prompt

I want to build a local, private chatbot app that runs on my own computer. The main idea is that I can upload my own documents—like PDFs, text files, and so on—to create a knowledge base, and then ask questions about them. It should have a simple web interface, probably built with Streamlit, for chatting and managing the files.

Please build it in Python. It needs to support popular open-source models like Llama or Qwen so I don't need to use an external API like OpenAI. I'd also love for it to have some 'agent' capabilities. For example, it should be able to use tools to search the web, do calculations, or even understand and talk about images I upload. Maybe it could generate images too.

You can use FastAPI for the backend API. If it's easier, setting the whole thing up with Docker would be great. The goal is to have a complete, runnable project that I can start using right away to chat with my private data.