Hi,
Sometimes I start with a simple conversation in ChatGPT, then gradually add more context and upload several documents. As the conversation grows, I realize it would make more sense as a project.
Not saying or implying your idea is invalid, but could you not ask the model to make Project instructions based on the chat, and then create a project based on what it gives you and move the chat into that project? After that the model should have access to the custom instructions and any reference files you provide. If I’m mistaken and you mean something else please feel free to correct me.