Build binary wheels for PyPI releases

[virgesmith]

The release workflow only ever built an sdist, so every pip install humanleague from PyPI had to compile the nanobind extension from source — which needs a toolchain, CMake and nanobind on the user's machine.

Changes

• wheels job — cibuildwheel across ubuntu-latest, windows-latest and macos-latest, uploading one artifact per platform.
• sdist job — uv build --sdist, unchanged in substance, just split out so it runs in parallel.
• deploy job — now needs: [wheels, sdist] and downloads their artifacts instead of building anything itself, then publishes the lot.
• workflow_dispatch trigger so the wheel build can be exercised without cutting a release. deploy is guarded with if: startsWith(github.ref, 'refs/tags/v'), so a manual run builds and uploads artifacts but does not publish.
• Removed the zip examples steps. They packaged an examples/ directory that does not exist in the repo and never has (git log -- examples is empty, and it isn't gitignored), so zip -r examples.zip examples/ would exit non-zero. Because they sat in deploy after uv publish, a tagged release would have published to PyPI and then gone red.

Open item

There is no [tool.cibuildwheel] section in pyproject.toml. The comment above the setup-uv step explains that build-frontend = "build[uv]" needs uv on the runner, but no such setting exists in the repo — cibuildwheel will use its default pip-based frontend, making that step redundant. Either add the config the comment assumes, or drop the comment and the step.

Worth doing a workflow_dispatch run on this branch before merging — that exercises wheels and sdist end to end while the tag guard keeps deploy from firing.

🤖 Generated with Claude Code

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 94.68%. Comparing base (01786ba) to head (c4b81ff).

Additional details and impacted files

@@           Coverage Diff           @@
##             main      #67   +/-   ##
=======================================
  Coverage   94.68%   94.68%           
=======================================
  Files          26       26           
  Lines        1035     1035           
=======================================
  Hits          980      980           
  Misses         55       55           

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.