Update docs to use NVIDIA Sphinx theme

[bdice]

Description

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

This replaces the previous Sphinx theme dependency, removes the legacy shared RAPIDS CSS/JavaScript injection where present, and regenerates dependency manifests.

Contributes to rapidsai/build-planning#300.

Validation

• Commit-time pre-commit hooks passed, including generated dependency files.
• Doxygen and sphinx-build -b dirhtml ./source _html -W passed in the CUDA 13.3 devcontainer.
• sphinx-build --builder doctest ./source _doctest -W passed all eight doctests.
• Rendered HTML loads the NVIDIA theme, uses the default left navigation, and contains no legacy shared RAPIDS asset URLs.

[copy-pr-bot]

Auto-sync is disabled for draft pull requests in this repository. Workflows must be run manually.

Contributors can view more details about this message here.

[bdice]

Rendered from 6b2e5ccc.

Main page

API reference

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Enterprise

Run ID: 82043d08-b375-4034-b684-355514677bf9

📥 Commits

Reviewing files that changed from the base of the PR and between 6b2e5cc and 5f01236.

📒 Files selected for processing (5)

• conda/environments/all_cuda-129_arch-aarch64.yaml
• conda/environments/all_cuda-129_arch-x86_64.yaml
• conda/environments/all_cuda-133_arch-aarch64.yaml
• conda/environments/all_cuda-133_arch-x86_64.yaml
• dependencies.yaml

✅ Files skipped from review due to trivial changes (1)

• conda/environments/all_cuda-129_arch-aarch64.yaml

🚧 Files skipped from review as they are similar to previous changes (4)

• conda/environments/all_cuda-133_arch-x86_64.yaml
• conda/environments/all_cuda-129_arch-x86_64.yaml
• conda/environments/all_cuda-133_arch-aarch64.yaml
• dependencies.yaml

---

📝 Walkthrough

Summary by CodeRabbit

• Documentation
  • Updated documentation branding to NVIDIA nvForest and refreshed the homepage title.
  • Switched the Sphinx HTML theme from pydata_sphinx_theme to nvidia_sphinx_theme, including theme options cleanup (removed the “X” icon link).
  • Simplified documentation assets by removing remote custom JS/CSS includes and using only the local custom.css.
  • Updated environment and dependency definitions so documentation builds install the new theme package.

Walkthrough

This PR updates documentation packaging and Sphinx configuration to use nvidia-sphinx-theme, renames the project title, adjusts generated document titles, and removes old RAPIDS header assets.

Changes

Documentation theme migration

Layer / File(s)	Summary
Dependency spec updates across conda environments and dependencies.yaml conda/environments/all_cuda-129_arch-aarch64.yaml, conda/environments/all_cuda-129_arch-x86_64.yaml, conda/environments/all_cuda-133_arch-aarch64.yaml, conda/environments/all_cuda-133_arch-x86_64.yaml, dependencies.yaml	Removes pydata-sphinx-theme and adds nvidia-sphinx-theme under a pip: subsection across the environment and dependency specs.
Sphinx theme, project title, and title strings in conf.py docs/source/conf.py	Changes the project name, switches the HTML theme, removes the X icon link, and updates LaTeX, man page, and texinfo titles to use the project variable.
Custom asset registration and header/index cleanup docs/source/conf.py, cpp/doxygen/header.html, docs/source/index.rst	Limits setup(app) to local custom.css, removes RAPIDS custom header includes, and updates the documentation landing-page heading.

Estimated code review effort: 2 (Simple) | ~10 minutes

Suggested labels: conda, improvement

Suggested reviewers: csadorf, jameslamb

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly summarizes the main change: switching docs to the NVIDIA Sphinx theme.
Description check	✅ Passed	The description matches the changeset and correctly describes the theme swap and docs cleanup.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

---

_{Comment @coderabbitai help to get the list of available commands.}