fix: handle scoped packages with _index on package root

[wkillerud]

Fixes #284

Like I mentioned in the issue, there's still a bug when I cmd/ctrl + click the link @use "@foo/bar"; where VS Code tries to open the file of that name. I wasn't able to figure out where and how to fix that.

[ghost]

All CLA requirements met.

[aeschli]

Thanks @wkillerud. I added another commit to fix the open. The reason was a unnecessary encoding of the @.

I updated the test in the following way

• @use '@foo/bar/baz resolves to node_modules/@foo/bar/_baz.scss
• @use '@foo/bar resolves to node_modules/@foo/bar/_index.scss

Please speak up, if I misunderstand how @use works

[wkillerud]

Nice, thank you!

@use '@foo/bar/baz resolves to node_modules/@foo/bar/_baz.scss

If _baz.scss exists, yes. Otherwise it might resolve to:

• node_modules/@foo/bar/baz.scss (non-partial)
• node_modules/@foo/bar/baz/_index.scss (where baz is another directory with an index file))

@use '@foo/bar resolves to node_modules/@foo/bar/_index.scss

Yes

[aeschli]

If _baz.scss exists, yes. Otherwise it might resolve to:

• node_modules/@foo/bar/baz.scss (non-partial)
• node_modules/@foo/bar/baz/_index.scss (where baz is another directory with an index file))

Yes, that's how it's implemented.