feat: 🎸 add scss support for tilde (~) imports

[kaisermann]

✅ Closes: #277

edit 1:
Just gotta do a test for it 😁

edit 2:
Tests are failing now, not sure why. See sass/node-sass-middleware#104 Can't use the done for renderSync runs.

Current challenge:
it seems the sass compiler doesn't pass an importer's returned value through the includePaths paths, so it needs to return an absolute path. We use the url and prev (source) arguments to resolve it , but, for some reason, the prev value is coming as stdin instead of the importer path.. Needed to pass file alongside the rest of the options.

edit 3:
Need to rewrite that importer, the logic is wrong. It will stop on the first node_modules found, even if there's no package with the specified path.

References:
https://github.com/matthewdavidson/node-sass-tilde-importer/blob/master/index.js
https://sass-lang.com/documentation/js-api#importer

[kaisermann]

Not sure why the windows test is failing 😢

[ghost]

@kaisermann Hi, do you know why the windows test isn't working? I didn't even know certain NodeJS modules/features are platform-dependent 😮

[kaisermann]

@GitGangGuy Nope, no idea. The file is there 🤷 However, it may work if I read it manually and use the { content } return API instead of { file }.