So, just like you said, rewrite the whole thing, THEN break it apart into bite size chunks that tell the story and feed it to others with acceptable and reasonable context.
It’s a skill that engineers need, and it pays dividends to all on the team, including you, when your coworkers ALSO start doing this back to you and you’re asked to review it.
And this is often how I proceed when working with an LLM as well. We build the whole thing, and if I think it needs to be split apart, then in another session I work with the LLM to break it apart into reasonable chunks.
This is knowledge that goes back to the beginning of software development - "Plan to throw [version] one away".
I think this could potentially become a good practice. LLMs make it so easy and cheap to just get it working and build that v1. Then you can play around with it and see if works and read the code about what could be better. Throw away the LLM generated version and now this is the part where human expertise comes in. Based on what you've learned from the v1, now guide the LLM more closely about how to write the thing and help guide it so that making small PRs that are easily reviewable and understandable are the output.