Context

The project currently tracks a uv.lock file that must be kept in sync with pyproject.toml. We want to remove the lock file entirely and instead use:

 - UV_NO_LOCK=1 — tells uv not to create or read from a lock file
 - UV_EXCLUDE_NEWER=<7-days-ago> — excludes packages published in the last 7 days

Definition of done

Remove lock file and ensure it is not re-created by any commands.

Pitfalls

We lose the ability to re-run a job and have it run with the exact package versions of the previous job.