use pyproject's docs for docs instead of requirements_docs.txt

[andrewgsavage]

• Closes # (insert issue number)
• Executed pre-commit run --all-files or pixi run lint --all-files with no errors
• The change is fully covered by automated unit tests
• Documented in docs/ as appropriate
• Added an entry to the CHANGES file

[codspeed-hq]

Merging this PR will not alter performance

⚠️ Unknown Walltime execution environment detected

Using the Walltime instrument on standard Hosted Runners will lead to inconsistent data.

For the most accurate results, we recommend using CodSpeed Macro Runners: bare-metal machines fine-tuned for performance measurement consistency.

✅ 448 untouched benchmarks
⏩ 448 skipped benchmarks¹

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_{Comparing andrewgsavage:docs (c655264) with master (0751fac)}

Footnotes

1. 448 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩