Reduce GitHub Pages deploy artifact noise by removing tracked Sphinx build outputs

[Copilot]

The pages build and deployment workflow was failing in the deploy job during Pages syncing_files. This change trims non-site build artifacts from the published tree so the Pages artifact contains only content intended for deployment.

• Remove tracked Sphinx build artifacts

  • Delete committed .doctrees/ contents, .buildinfo, objects.inv, and Python bytecode under _static/__pycache__/.
  • Remove binary/intermediate files that do not belong in a GitHub Pages artifact.

• Prevent reintroducing deploy noise

  • Extend .gitignore to exclude Sphinx/Python build outputs going forward:
    • *.pyc
    • __pycache__/
    • .buildinfo
    • .doctrees/

• Effect on Pages deployment

  • Reduces unnecessary files in the uploaded Pages artifact.
  • Avoids publishing Python/Sphinx internals as static site content.

*.pyc
__pycache__/
.buildinfo
.doctrees/