feat: Extend webpack plugin for supporting contenthash

[Danielku15]

Issues

Fixes #1348

Proposed changes

• Better handling of non-web files
• Ensure webpack dependencies can be serialized and the runtime is cached (needed for hot reload)
• Splitup of webpack plugin into multiple files for better code structure
• Ensure font and soundfont assets are registered within webpack (required for dev server)
• Do lookup of worklet chunk files during runtime and add runtime module for accessing file names (required for contenthash)

Tested with the alphaTab website.

Checklist

• I consent that this change becomes part of alphaTab under it's current or any future open source license
• Changes are implemented
• Existing builds tests pass
• New tests were added

Further details

• This is a breaking change
• This change will require update of the documentation/website