Within-section navigation missing for smaller screens, global contents difficult to navigate.

Documentation

Problem

Within a documentation section (I'm using that term to refer to sub-documents like, say, the tutorial, not sure if there is an official term), there is currently no way to go "up" a level to see the contents of that section when not using a full width screen:

Full width screens have breadcrumbs at the top

The "table of contents" link takes you back to the global contents, which are not usable, as they contain every header from every document in the docs - take a scroll if you haven't in awhile: https://docs.python.org/3/contents.html

It's also not obvious which document you are in, as "table of contents" is ambiguous - the only place that "tutorial" is present is in the URL.

This makes it quite challenging to navigate the docs on mobile, or when splitting a screen and reading in a narrow window.

Desired solution

I would like...

• the sidebar "Table of Contents" to be replaced with the title of current document section when one is within a document section (eg. /{version}/tutorial/interpreter.html), and with a link to the global ToC when one is in a section ToC (eg. /{version}/tutorial/).
• The maxdepth of the global ToC to be reduced to 2 to make it usable

I will follow on with a PR momentarily...

Linked PRs

• gh-123453

Start by reviewing the documentation sidebar navigation, the global table of contents, and section URLs such as /{version}/tutorial/interpreter.html and /{version}/tutorial/. Done means narrow screens identify the current section, provide navigation back to its section contents, link section ToCs to the global ToC, and limit the global ToC maxdepth to 2. A linked pull request is already referenced in the issue.