Free Gemini solution with Copilot:
Instead of using {activeNote} in the prompt, you add the links you want and may need to customize prompt.
I didn’t try it with many notes and was not really happy with Smart Connections for full vault usage or Msty app’s embedding model to get good results, but I have a large vault with lots of text.
It’s possible that paid embedding models can do a better job, or otherwise the mentioned Gemini solution can handle one million token input so a few files it will be able to handle but will be slower too if the prompt is too complex.