Configure builds

- Create `dartsass.builds` initializer and add all Sass files to be compiled. See https://github.com/rails/dartsass-rails#configuring-builds
- Create .keep
- Update manifest file to use /builds directory
- Ignore /builds

.gitignore

@@ -16,6 +16,8 @@
 /tmp
 
 /public/assets
+/app/assets/builds/*
+!/app/assets/builds/.keep
 /test/wraith/wip*
 shots/*
 /coverage

app/assets/config/manifest.js

@@ -1,20 +1,4 @@
 //= link_tree ../images
 //= link application.js
 //= link webchat.js
-//= link application.css
-//= link components/_back-to-top.css
-//= link components/_banner.css
-//= link components/_contents-list-with-body.css
-//= link components/_download-link.css
-//= link components/_error-message.css
-//= link components/_figure.css
-//= link components/_important-metadata.css
-//= link components/_published-dates.css
-//= link components/_publisher-metadata.css
-//= link views/_guide.css
-//= link views/_html-publication.css
-//= link views/_manual.css
-//= link views/_published-dates-button-group.css
-//= link views/_service_manual_guide.css
-//= link views/_specialist-document.css
-//= link views/_travel-advice.css
+//= link_tree ../builds

config/initializers/dartsass.rb

@@ -0,0 +1,23 @@
+APP_STYLESHEETS = {
+  "application.scss" => "application.css",
+  "components/_back-to-top.scss" => "components/_back-to-top.css",
+  "components/_banner.scss" => "components/_banner.css",
+  "components/_contents-list-with-body.scss" => "components/_contents-list-with-body.css",
+  "components/_download-link.scss" => "components/_download-link.css",
+  "components/_error-message.scss" => "components/_error-message.css",
+  "components/_figure.scss" => "components/_figure.css",
+  "components/_important-metadata.scss" => "components/_important-metadata.css",
+  "components/_publisher-metadata.scss" => "components/_publisher-metadata.css",
+  "views/_guide.scss" => "views/_guide.css",
+  "views/_html-publication.scss" => "views/_html-publication.css",
+  "views/_manual.scss" => "views/_manual.css",
+  "views/_published-dates-button-group.scss" => "views/_published-dates-button-group.css",
+  "views/_service_manual_guide.scss" => "views/_service_manual_guide.css",
+  "views/_specialist-document.scss" => "views/_specialist-document.css",
+  "views/_travel-advice.scss" => "views/_travel-advice.css",
+}
+
+all_stylesheets = APP_STYLESHEETS.merge(GovukPublishingComponents::Config.all_stylesheets)
+Rails.application.config.dartsass.builds = all_stylesheets
+
+Rails.application.config.dartsass.build_options << " --quiet-deps"