gkamradt/langchain-tutorials ? reverse-engineered prompt

Build me a clean GitHub repo of Jupyter notebooks that teaches LangChain from scratch, like a friendly cookbook for beginners and people who want real examples.

I want a main landing README that explains the learning path, then separate notebooks for the core concepts and common use cases, like summarizing text, chatting with documents, extracting structured data, working with chat APIs, loaders, chains, agents, and simple chatbot ideas. Keep it easy to follow, with short explanations, code cells that run, and clear sections for what each notebook is showing.

Please make it feel like a tutorial collection people can browse and learn from, not a formal library. Include a simple requirements file and a summary page so someone new can find the right place to start. If anything depends on newer LangChain docs, look up the current docs online if you need to.