Make `uv init` options more user-friendly

[dandavison]

Hi, thanks for uv, it's looking great.

I think this should be made a bit more user-friendly, by indicating what the defaults are, and perhaps by making it clearer which subsets make sense to be used together.

Options:
      --package        Set up the project to be built as a Python package
      --no-package     Do not set up the project to be built as a Python package
      --app            Create a project for an application
      --lib            Create a project for a library

[zanieb]

Sure we can add a bit more context to the CLI reference, it's a bit sparse since these options are new. I'd recommend using the long-form help (uv help init) to see the more details.

Also, the documentation on this should be relatively clear https://docs.astral.sh/uv/concepts/projects/#creating-projects

[astrojuanlu]

Related: #8311