Edit Page Button

[DLu]

Adds an edit page button to all content pages on docs.hello-robot.com including those included through submodules.

Demo

EditButton.mp4

Notes

• If only the changes to mkdocs.yml were included (without the hooks part), the edit button would appear on all the pages, but have the inappropriate link for most of them.
• I wanted there to be a way to have the edit_uri configuration not be hard-coded to the branch name, but the edit_uri_template variable has very limited fields to include.
• This PR adds a dependency on the Python library GitPython, which is not strictly necessary, but easier than parsing .gitmodules by hand.
• I have included the associated uv.lock changes that were autogenerated, but I'm not super familiar with its intricacies.

[hello-binit]

Thanks for adding this!