Prune stub files in docs/docsite

[oraNod]

A few years ago @samccann and I restructured the monolithic "User Guide" into more logically organized sections like the playbook guide. Rather than deleting RST files from the User Guide, we created stub files using the :orphan: tag. This allowed us to avoid adding to the httpd redirects configuration.

These stub files still exist but are no longer needed. In fact the need for most stub pages has been completely replaced by ansible_redirects.toml.

Additional reasons to remove the stub files:

• Add unnecessary work for sphinx-build.
• Add complexity to the docsite for contributors when looking for documentation source files.
• Result in noisy content in various output such as llms.txt. For example there are lots of orphan pages that are generated into llms-full.txt such as the following:

:orphan:

Windows Remote Management
=========================

This page has moved to :ref:`windows_winrm`.

You can see all the orphans with: find . -path docs/docsite/rst -o -name "*.rst" -type f -exec grep -l ":orphan:" {} \;

For each directory / file, we should confirm a corresponding entry is in ansible_redirects.toml and then remove. I'm not sure if we should give the collections directory the same treatment or not but we can figure that out and maybe do it as a follow on.

Also this will result in 404s for ansible-core documentation because that project doesn't use the redirects. It's not a big deal though. We can add some straightforward RTD redirects for paths such as user_guide.