Improve webpack config for HtmlBundlerPlugin

[webdiscus]

Hello,

I'm the author of the html-bundler-webpack-plugin.
I want to improve the Webpack configuration to save processed JS and CSS in separate folders.

Defaults Webpack places generated HTML, JS and CSS files into directory specified in the output.path Webpack option.
After running npm run bundle, the src/fontra/client/ directory contains a mix of generated HTML, CSS, and JS files.

This PR allows configuring the Bundler Plugin to save JS and CSS, resolved in HTML, into separate directories:

• CSS -> src/fontra/client/css/
• JS -> src/fontra/client/js/

See js and css plugin options.

Hashed file names ensure that the output file name is unique, avoiding conflicts with copied files.
Now, the root web directory src/fontra/client/ contains only generated HTML files.

All assets will be loaded in a browser:

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