docs: 📝 extend supervision installation methods

[onuralpszr]

Description - Doc changes

This change introduce alternative installation methods of supervision for show audience other tooling too.

[LinasKo]

Love it, this is great.

Do you think we should mention uv add supervision as well? My impression was that it's moving towards using add over pip install.

[onuralpszr]

Let's keep both because they have different use case, "add" is for project like rye/poetry "uv pip" just directly installs no matter. We can mention difference between add or pip way If you like just simple one line

         ```bash
        uv pip install supervision
        ```
        
        For uv projects

        ```bash
        uv add supervision
        ```

What do you think?

[LinasKo]

@onuralpszr, sure. With tiny formatting changes:

uv pip install supervision

For uv projects:

uv add supervision