Update Sphinx configuration to modern standards and add CI documentation build

[Copilot]

Sphinx documentation was failing to build cleanly due to deprecated API usage and configuration issues.

Changes

Configuration modernization (docs/conf.py)

• Replace deprecated master_doc with root_doc
• Convert source_suffix from string to dictionary format
• Remove deprecated html_theme_path call (unnecessary with modern sphinx_rtd_theme)
• Replace manual Mock class with autodoc_mock_imports (Sphinx's native mocking mechanism)
• Suppress autodoc.import_object warnings for dependencies that can't be imported during doc build

RST formatting (docs/index.rst)

• Fix title underline length mismatch

CI/CD integration (.github/workflows/tests.yml)

• Add docs job to build documentation on every PR
• Install Sphinx and sphinx_rtd_theme dependencies
• Build HTML documentation and upload as artifact
• Include docs job in failure notification system

Result

Documentation now builds cleanly with zero warnings on Sphinx 9.1.0:

cd docs && make html
# Running Sphinx v9.1.0
# ...
# build succeeded.

The documentation build is now automated in the CI pipeline and will run on every pull request, ensuring documentation changes don't break the build process.

Original prompt

Update docs to current sphinx standards and make it work again

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✨ Let Copilot coding agent set things up for you — coding agent works faster and does higher quality work when set up for your repo.

[csett86]

@copilot In addition, build the documentation on every PR in github actions tests.yml

[Copilot]

@copilot In addition, build the documentation on every PR in github actions tests.yml

Added a docs job to .github/workflows/tests.yml that builds the documentation on every PR. The job installs Sphinx and sphinx_rtd_theme, builds the HTML documentation, and uploads it as an artifact. The documentation build is now part of the CI pipeline alongside tests and package builds. (commit b4680f3)