perf: replace dev middleware with a lightweight version

[chenjiahan]

Summary

Replace webpack-dev-middleware with rsbuild-dev-middleware.

rsbuild-dev-middleware is forked from webpack-dev-middleware, and it is designed for Rsbuild. We will remove all unused options / features from this package to make it smaller and more performant. Eventually rsbuild-dev-middleware will be merged into @rsbuild/core

This PR introduces rsbuild-dev-middleware v0.1.0, the bundle size has been reduced from 348 KB to 181 KB.

Related Links

https://github.com/chenjiahan/rsbuild-dev-middleware

Checklist

• Tests updated (or not required).
• Documentation updated (or not required).

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