Add Windows ARM64 wheel support

[ssss141414]

Summary

• add native Windows ARM64 CI coverage for Python 3.11-3.13 on windows-11-arm
• build win_arm64 wheels in the existing tag-triggered cibuildwheel release workflow
• remove the obsolete nose build hook and stabilize two ARM64-exposed test behaviors

Local validation

• built annoy-1.17.3-cp313-cp313-win_arm64.whl on native Windows ARM64
• verified the extension PE machine is ARM64 (0xAA64)
• clean-installed the wheel outside the source checkout and ran native functional smoke tests
• ran the upstream test suite: 107 passed, 1 skipped

Publication behavior

The wheel is not committed to this repository and this PR does not publish to PyPI. The existing publish workflow remains tag-push-only; after merge, a maintainer-created release tag can build and publish the ARM64 wheel through the normal release path.

[ssss141414]

Hi,

The annoylib.h change is needed because the existing angular-distance tests fail on native Windows ARM64 without it.

For two byte-identical vectors, the angular distance should be exactly zero. However, with the optimized MSVC ARM64 build, the dot product and cached norm can have slightly different floating-point rounding. As a result, this expression:

2.0 - 2.0 * pq / sqrt(pp * qq)

returns a small positive value instead of zero. The observed self-distances were approximately 0.0001957 and 0.0002183.

This causes the existing test_include_dists and test_include_dists_check_ranges tests to fail. The memcmp check only handles vectors with identical stored representations and returns the mathematically correct distance of zero before evaluating the floating-point formula.

Without this change, the Windows ARM64 wheel still builds and imports, but its native CI test suite reports 2 failures. With the change, those tests pass.

This is therefore a runtime correctness fix exposed by Windows ARM64 rather than a wheel-build configuration change. If preferred, it can be submitted as a separate prerequisite bug-fix PR, with the Windows ARM64 wheel PR depending on it.

Thank you!

[ssss141414]

Hi annoy maintainers,

I'm from Microsoft and recently I'm working on improving Python ecosystem support for Windows on Arm. So I also adds CI support for Windows ARM64. Could you please help to review?

Thanks.