Add UV as the installer for hatch envs

UV can be used with a lot of different tools as the backend installer. It really speeds things up for nox environments. [Hatch also allows you to set uv as the default installer](https://hatch.pypa.io/1.13/how-to/environment/select-installer/) We could consider ass this to our template to speed up things. i'm going to test it out before the workshop but with nox it's great and doesn't change much other than speed! To use, the setup would just be to add this (to our pyproject.toml.jinja file): ``` [tool.hatch.envs.default] installer = "uv" ```