Replace webpack with rspack

[silverwind]

Given that this bundler is almost a drop-in replacement to webpack, it might be worth switching. So far it seems everything is working, but more testing is needed, so I'm setting draft.

• Dev build time is reduced from 10s to 5s
• Prod build time is reduced from 16s to 10s
• JS output size is reduced from 21.3MB to 19.8MB
• CSS output size is increased from 778kB to 818kB

[silverwind]

One related update added here: https://github.com/sindresorhus/add-asset-webpack-plugin/releases/tag/v3.1.0 includes type definitions, so I removed the type stub for that package.

[silverwind]

This is working very well in my testing, chunk loading and all works as expected. It supports the webpack comments and variables, so from my point of view, this is ready.