fix: mark webpack as optional peer dependency

[chenjiahan]

Summary

• Added @rspack/core as an optional peer dependency
• Updated peerDependenciesMeta to mark both @rspack/core and webpack as optional
• The README.md now mentions that babal-loader can be used with both webpack and Rspack

[Copilot]

Pull request overview

This PR enables babel-loader to work with both webpack and Rspack by marking both as optional peer dependencies. This allows users to choose either bundler without requiring both to be installed.

Changes:

• Added @rspack/core as an optional peer dependency with version range ^1.0.0 || ^2.0.0-0
• Marked both @rspack/core and webpack as optional in peerDependenciesMeta
• Updated README.md description to mention Rspack support alongside webpack

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
package.json	Added @rspack/core as optional peer dependency and configured peerDependenciesMeta to mark both webpack and @rspack/core as optional
README.md	Updated package description to indicate support for both webpack and Rspack

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[nicolo-ribaudo]

Thank you! Could you update the tests to test rspack compatibility?

[chenjiahan]

Sure! I have updated all test cases to test both webpack and Rspack.

[chenjiahan]

@nicolo-ribaudo When you have a chance, please take a look. Thanks!

[nicolo-ribaudo]

Thank you! @JLHwung could you also take a look since you have more experience with this codebase?

[JLHwung]

Great work! Thank you.