[Remove Node.js] Use dart-sass for SCSS

[malparty]

inherit #431

Note

This issue does NOT include any code change in the Rails template (yet), as these will be based on the RFC results.

Why

SCSS build currently relies on Node.js.

Checklist

• POC in CX (side branches)
• Presentation of learnings (WIP in https://docs.google.com/presentation/d/1BOXkg7wGwSkzdqILP3VH7XDiXNDsXiR719jumeICktQ/edit#slide=id.gf7533c37e2_3_0 )
• RFC in GitHub discussion

Insight 📝

The cssbundling-rails gem relies on Node.js.
[Rails Guides](https://guides.rubyonrails.org/asset_pipeline.html#[dartsass-rails](https://guides.rubyonrails.org/asset_pipeline.html#dartsass-rails)) recommend using the dartsass-rails to remove Node.js dependency.

./bin/bundle add dartsass-rails
./bin/rails dartsass:install

Note

It turns out import-maps is limited to JS and won’t let you pin other assets like SCSS or images.
rails/importmap-rails#80

“If you need Node for anything, I'd use it for everything. The benefit of import maps is that it provides a path with no Node at all. cssbundling-rails and jsbundling-rails is a great combo to use with Bootstrap 👍”
DHH – [source](rails/importmap-rails#107 (comment))

Who Benefits?

• Developers for the knowledge
• Future clients' projects for improved tooling decisions.

[malparty]

Issue started in https://github.com/nimblehq/cx-web/pull/757