Move important code out of util

[josephjclark]

A pattern in the gen project at the moment is to over-rely on the util folder (and

This makes it it hard to find important code.

The util pattern should apply standalone, re-usable pure functions. IMO you should be able to fully understand a project without looking at anything in utils.

In this repo, lots of key functionality is buried in utils. For example, the prompts which get sent to the models are in utils. But prompts is one of the most important parts of the project, one of the things I want to easily discover! They should be pulled out into prompts.py. Ditto for models.

To be fair, this issue might just be to move prompys.py and models.py out of the utils folder 🤷