Crate-docs-theme

-----------------
- Fixed building docs at ``crate/crate`` by removing stray ``README.md``
- Furo: Started using vendorized colors to make mixins work
- Furo: Started using non-vendorized head variables
- Templates: Use proper ``base.html`` and clean up ``page.html``

-----------------
- Updated to most recent Furo
- Added dark theme mode from Furo

Thanks, msbt.

-----------------
- Re-added menu item about Cloud CLI (croud)

-----------------
- Webpack: Use legacy configuration options with Sass 16
- Navigation: Brought back ESI
- Chore: Cleaned up styles

-----------------
- RTD: Add compatibility fixes for upstream changes at Read The Docs,
`enabling Read the Docs Addons by default`_.
- RTD: Fix CSS to hide RTD-injected elements: Ads, fly-out, and footer.
- RTD: Vendorize ``sphinx-build-compatibility`` to permit publishing
``crate-docs-theme`` to PyPI.
- RTD: Fix inquiring active project versions.
The v2 API returns or started returning inactive builds (PR numbers) in
inquiries to active project versions. The v3 API works better, so the
code in ``sphinx-build-compatibility`` has been adjusted correspondingly.
- `New GitHub Issues`_: Make link checker ignore HTML anchor references
on GitHub after switching to the evolved GitHub Issues. This includes an
update to ``sphinx>=7.1,<9``, to respect the
``linkcheck_anchors_ignore_for_url`` configuration setting.

.. _enabling Read the Docs Addons by default: https://about.readthedocs.com/blog/2024/07/addons-by-default/
.. _New GitHub Issues: https://github.blog/changelog/2024-10-01-evolving-github-issues-public-beta/

-----------------
- Added a "Academy" menu item
- Applied spacing to article footer