fix!: changed default export to named export

[hardfist]

BREAKING CHANGE: change rspack-dev-middleware & rspack-plugin-html default export to named export

fixes #2944 #2851

Related issue (if exists)

Summary

🤖 Generated by Copilot at 65f6637

This pull request changes the export and import syntax of several packages in the rspack project to avoid using default exports, which can cause compatibility and consistency issues. The affected packages are @rspack/dev-middleware, @rspack/dev-server, and @rspack/plugin-html.

Walkthrough

🤖 Generated by Copilot at 65f6637

• Remove default exports and use named exports instead for rdm function and middleware module in @rspack/dev-middleware package (link)
• Update import syntax for rdm function and getRspackMemoryAssets function in server.ts of @rspack/dev-server package to use named imports from @rspack/dev-middleware package (link)
• Remove default export of HtmlRspackPlugin class in @rspack/plugin-html package and use named export instead (link)