Update copier template

We should update to the latest [python copier template](https://github.com/DiamondLightSource/python-copier-template). This will switch us from using `pip` to `uv`, add a `uv.lock`, and may require other changes, such as reformatting the `pyproject.toml` for uv.
## Acceptance Criteria
- We are using the latest python copier template
- Everything either works as it did before, or differences are documented

Start by comparing the current repository setup with the latest python-copier-template, focusing on pyproject.toml and the existing pip workflow. Check the template's uv configuration and determine what changes are needed to add uv.lock. Done means the latest template is in use, existing behavior still works or differences are documented, and the project can be run and tested successfully.

Written by the indexing model from the issue text.