build and publish a wheel

[dimbleby]

Currently you are only publishing an sdist. Publish a wheel also.

[cursor]

PR Summary

Low Risk
Build configuration change with no impact to code logic or runtime behavior; enables an additional standard package format for distribution.

Overview
Removes the --format sdist flag from the poetry build command in the Makefile, enabling the build to produce both source distributions and wheels by default. Updates the corresponding GitHub Actions workflow step name to reflect that both package formats are now built.

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[CLAassistant]

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[dimbleby]

I will not be signing a CLA. You are welcome to this contribution, take it or leave it.