[seddonym]

Summary

Routine release PR per CONTRIBUTING.rst's release process - bumps the version to 3.18 and finalizes the CHANGELOG.rst entry.

Notable fixes in this release (see #327):

• Missing macOS wheels for regular (non-freethreaded) Python 3.14+.
• Missing Linux aarch64 wheels for Python 3.15 (now built on a native arm64 runner).
• Linux armv7/s390x/ppc64le and musllinux wheels for Python 3.15 are still unavailable (documented explicitly rather than silently skipped), pending upstream Docker image support.

Test plan

• CI passes on this branch.
• After merging, tag v3.18 and push the tag per CONTRIBUTING.rst step 11-12, which triggers the release workflow to build and publish wheels to PyPI.
• Spot-check PyPI after publish that Linux aarch64 cp315 wheels are present this time.

🤖 Generated with Claude Code

[codspeed]

Merging this PR will not alter performance

✅ 26 untouched benchmarks
⏩ 23 skipped benchmarks¹

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_{Comparing release-v3.18 (c019ec7) with main (6876d13)}

Footnotes

1. 23 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. ↩