ci: Update tox and handle generic classifiers

[sentrivana]

huey has moved from version-specific classifiers like "Programming Language :: Python :: 3.13" to just "Programming Language :: Python :: 3". We use specific classifiers to figure out the concrete Python versions the package supports, and ignore the global ones, which made toxgen report that the latest huey release had no supported Python versions.

Changing this so that if there are no specific classifiers and no requires_python, we also check for the global "Programming Language :: Python :: 3" classifier and assume the package supports all Python 3 versions in that case. In case that's not true, we fine-tune the Python versions to use via the config.

[github-actions]

Semver Impact of This PR

🟢 Patch (bug fixes)

📋 Changelog Preview

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Entries from this PR are highlighted with a left border (blockquote style).

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New Features ✨

• feat(asyncio): Add on-demand way to enable AsyncioIntegration by sentrivana in #5288

Bug Fixes 🐛

• fix(ai): redact message parts content of type blob by constantinius in #5243
• fix(clickhouse): Guard against module shadowing by alexander-alderman-webb in #5250
• fix(gql): Revert signature change of patched gql.Client.execute by alexander-alderman-webb in #5289
• fix(grpc): Derive interception state from channel fields by alexander-alderman-webb in #5302
• fix(litellm): Guard against module shadowing by alexander-alderman-webb in #5249
• fix(pure-eval): Guard against module shadowing by alexander-alderman-webb in #5252
• fix(ray): Guard against module shadowing by alexander-alderman-webb in #5254
• fix(threading): Handle channels shadowing by sentrivana in #5299
• fix(typer): Guard against module shadowing by alexander-alderman-webb in #5253

Documentation 📚

• docs(metrics): Remove experimental notice by alexander-alderman-webb in #5304
• docs: Update Python versions banner in README by sentrivana in #5287

Internal Changes 🔧

Release

• ci(release): Bump Craft version to fix issues by BYK in #5305
• ci(release): Switch from action-prepare-release to Craft by BYK in #5290

Other

• chore(gen_ai): add auto-enablement for google genai by shellmayr in #5295

• ci: Update tox and handle generic classifiers by sentrivana in #5306

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