Support resolver

[mizdra]

Allow @import '~bootstrap'; to resolve. Also, for users using the import alias of webpack or vite, allow for resolution using the imports field in package.json.

References

• Webpack
  • https://webpack.js.org/configuration/resolve/#resolvealias
• Vite
  • https://vitejs.dev/config/shared-options.html#resolve-alias
• Sass
  • https://github.com/webpack-contrib/sass-loader#resolving-import-at-rules
• Less
  • https://github.com/webpack-contrib/less-loader#webpack-resolver
  • https://github.com/less/less.js/blob/eefe33a47f6fdcc228817df7435a1770ce9e51ea/packages/less/src/less/environment/file-manager-api.js
  • https://github.com/webpack-contrib/less-loader/blob/d74f740c100c4006b00dfb3e02c6d5aaf8713519/src/utils.js#L44
• Node.js
  • https://nodejs.org/api/packages.html#subpath-imports

[mizdra]

• dart-sass has two APIs: Legacy API and Modern API.
• The Modern API does not implement a sufficient interface to implement custom resolvers.
  • ref: https://github.com/sass/sass/issues/3247
• The Legacy API, on the other hand, implements a sufficient interface.
  • https://github.com/sass/sass/blob/8228f433ce884ec6c70fdbffba4bab6e66296d31/js-api-doc/legacy/importer.d.ts#L92-L96
• enhanced-typed-css-modules uses the Modern API.
• Therefore, to implement a custom resolver, we must first switch to the Legacy API.

[mizdra]

First, we should refactor transformer.ts.

[mizdra]

Completed! :tada::tada::tada: