resolve.alias for internal dependencies does not work when src/index.{js,ts} isn't present

[ext]

resolve.alias is automatically configured to setup resolve.alias to map internal monorepo packages to it's src/index.{js,ts} but this breaks down when the file does not exist and when main points to a different file.

Example:

"main": "src/theme.scss"

This will be resolvable when using the actual package but not when importing it with Vite (using this config).

Unsure if this mapping is actually needed or if it can be removed altogether, if still needed the mapping should be more intelligent preferably by understanding both subpackage exports from exports and fields such as main.