## Summary
- align the PyO3 runtime and build ABI floor with the declared Python
3.10 minimum
- add a regression test that keeps both ABI features synchronized with
`requires-python`
## Root cause
The Python 3.10 support-floor update originally changed PyO3 to
`abi3-py310`, but a later dependency update reverted both PyO3 features
to `abi3-py39`. Published Windows wheels were consequently tagged
`cp39-abi3` while importing `PyCMethod_New`, a stable-ABI procedure
absent from CPython 3.9.0 and 3.9.1. Windows reports that mismatch as
“The specified procedure could not be found” while loading `_lancedb`.
Restoring `abi3-py310` makes the wheel tag and native imports agree with
the package metadata and prevents future wheels from advertising
unsupported Python 3.9 compatibility.
## Validation
- `uv run --extra tests pytest python/tests/test_package_metadata.py -q`
- `uv run --extra tests --extra dev ruff format --check .`
- `uv run --extra tests --extra dev ruff check .`
- `cargo fmt --all`
- `cargo check --quiet -p lancedb-python`
- `uvx --from maturin==1.12.4 maturin build --profile ci` (built
`lancedb-0.37.1b0-cp310-abi3-manylinux_2_34_x86_64.whl`)
Fixes#2051
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Co-authored-by: Gatefixer <313497061+lancedb-gatefixer[bot]@users.noreply.github.com>
lancedb-gatefixer[bot]