feat: add React Compiler support for SelectPanel

[joshblack]

Closes #

Adds React Compiler support for SelectPanel by removing it from the compiler unsupported list. Updates the empty-state test fixture so it models an async empty load completing under compiler-enabled tests.

Changelog

New

• React Compiler support for SelectPanel

Changed

• Updated SelectPanel empty-state test coverage to be compatible with React Compiler

Removed

• Removed SelectPanel from the React Compiler unsupported list

Rollout strategy

• Patch release
• Minor release
• Major release; if selected, include a written rollout or migration plan
• None; if selected, include a brief description as to why

Testing & Reviewing

• npx eslint --no-cache packages/react/src/SelectPanel/**/*.{ts,tsx}
• npm test -- --run packages/react/src/SelectPanel/SelectPanel.test.tsx packages/react/src/SelectPanel/SelectPanel.types.test.tsx
• npm run build && npm test -- --run && npm run type-check && npm run lint && npm run lint:css && npm run format:diff
• Verified Storybook responds locally

Merge checklist

• Added/updated tests
• Added/updated documentation
• Added/updated previews (Storybook)
• Changes are SSR compatible
• Tested in Chrome
• Tested in Firefox
• Tested in Safari
• Tested in Edge
• (GitHub staff only) Integration tests pass at github/github-ui (Learn more about how to run integration tests)

[changeset-bot]

🦋 Changeset detected

Latest commit: 14355bb

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@primer/react	Patch

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[github-actions]

⚠️ Action required

👋 Hi, this pull request contains changes to the source code that github/github-ui depends on. If you are GitHub staff, test these changes with github/github-ui using the integration workflow. If this doesn't work, you can also use the original workflow here. Check the integration testing docs for step-by-step instructions. Or, apply the integration-tests: skipped manually label to skip these checks.

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