Use SPDX license metadata

[BeauDevCode]

Summary:

• Updates setup.py to use the Apache-2.0 SPDX license expression.
• Keeps the License :: OSI Approved :: Apache Software License PyPI classifier for downstream compatibility and license-scanner support.

Validation:

• python setup.py --license - returned Apache-2.0.
• GitHub CI checks are currently passing.

Related issue:

• Closes Change license classifier in setup.py to use SPDX license term #1346

Risk:

• Low; packaging metadata-only change with no runtime code changes.

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[gemini-code-assist]

Code Review

This pull request updates the license string in setup.py to 'Apache-2.0' and removes the corresponding PyPI classifier. Feedback suggests retaining the 'License :: OSI Approved :: Apache Software License' classifier, as removing it can break downstream package consumers and automated compliance scanners that rely on standard PyPI classifiers.

[gemini-code-assist]

Removing the License :: OSI Approved :: Apache Software License classifier can break downstream package consumers and automated compliance scanners. Many enterprise dependency analysis tools and security scanners rely strictly on standard PyPI classifiers to verify license compliance. Removing this classifier can cause the package to be flagged as having an "unspecified" or "unknown" license. Additionally, PyPI's search and filtering features still rely on these classifiers. It is highly recommended to retain this classifier alongside the updated license field.

Suggested change

	'Intended Audience :: Science/Research',
	'License :: OSI Approved :: Apache Software License',
	'Operating System :: MacOS',
	'Intended Audience :: Science/Research',
	'License :: OSI Approved :: Apache Software License',
	'Operating System :: MacOS',

[mhucka]

@BeauDevCode Thank you for this contribution!

[mhucka]

Looks good.

[mhucka]

Fixes #1347.