Or maybe just a way to use chatgpt/Claude with files , and get accurate references to the page/paragraph in the source?

Claude/ChatGPT still end up making things up when they can't find anything, notebook is much better to 99% reply based on quotes. But yes a backup is to use Claude and grep, but not quite the same.

It's cumbersome to have llm duplicate all quotes and still get good response. Else you get no visibility into your sources.