test: Rollup integration tests

[timfish]

This PR:

• Moves the Sentry configs to separate reusable files
• Adds tests for Rollup v3 + v4
  • These use JavaScript config files rather than TypeScript because Rollup only supports TypeScript on the latest Node versions

[github-actions]

Semver Impact of This PR

🟢 Patch (bug fixes)

📋 Changelog Preview

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New Features ✨

• Use crypto.randomUUID rather than uuid by timfish in #892

Internal Changes 🔧

• Rollup integration tests by timfish in #897

• New integration tests by timfish in #896
• Remove lerna by timfish in #895
• Migrate to Vitest by timfish in #894

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[timfish]

This was key to fixing the Windows line endings snapshot issues.

Without this, git on Windows by default checks out all files with modified line endings!

[andreiborza]

😬 nice find