Update docs to use NVIDIA Sphinx theme

[bdice]

Description

Updates the deployment documentation to use nvidia_sphinx_theme with the theme's default left navigation.

This replaces the previous Sphinx theme and custom RAPIDS logo/navigation assets, removes the legacy shared RAPIDS CSS/JavaScript injection, adds the GitHub icon, and aligns the landing-page branding with the other NVIDIA RAPIDS documentation.

Contributes to rapidsai/build-planning#300.

Validation

• uv lock --check and a frozen dependency sync passed.
• sphinx-build -E -b dirhtml source build/linux-dirhtml -W --keep-going -n passed on Linux.
• Targeted pre-commit hooks passed.
• Rendered HTML uses the default NVIDIA logo and left navigation, includes the GitHub icon, and contains no legacy shared RAPIDS asset URLs.

[bdice]

Rendered from 9118d33.

Main page

[josephine-wolf-oberholtzer]

I'm not in the approvers list, but LGTM.

[jayavenkatesh19]

I spent some time looking through the Read the Docs build, and I noticed two things that are missing after this change (intentional or otherwise):

• Nightly and Stable version switcher: The deleted nav.js added a selector in the page to jump between nightly/stable doc versions.
• The Docs Home and Deployment Home links on the left navbar added by the same nav.js

I think not having links to the general RAPIDS and deployment docs is alright, but we might want to keep the Nightly/Stable version switcher. CCing @jacobtomlinson for his opinion about this.

Other than this, all functionality seems to be intact and good to go!

[bdice]

Oh interesting! For all other projects, the nightly/stable switcher and other nav links are added when we deploy docs.rapids.ai. This project is different, it seems.

[jacobtomlinson]

Here are some screenshots of some defects we've found

Purple headers

Some headers are still purple, I think this is some inline CSS.

Secondary sidebar not hiding

Some pages have the secondary sidebar disabled but this is not respected in the new theme and leads to dead whitespace on the right

Stable/Nightly switcher and Home buttons have gone

These navigation elements are missing

Tag underscores in sidebar

Tag links have underscore in between

Nav changes

The old theme has both top bar navigation for top level sections and left sidebar navigation for subsections. The new theme uses the sidebar only for all navigation. We might need to think a little about how we structured out navigation. For example the coda/pip/wsl pages are not showing on the nav on the left in the local section.

@bdice we are happy to take ownership of this PR and push fixes. We appreciate you kicking the ball off here but know you have a ton of these PRs to follow up on.

[bdice]

@jacobtomlinson Great, please take this and fix the issues you described, then merge when you're happy. Much appreciated!