Merge branch 'main' into browser

* main: (162 commits)
  Move source and test files to namespaced subdirectories
  Update Dart Sass version and release
  Update Dart Sass version and release
  Update Dart Sass version and release
  Update Dart Sass version and release
  Update Dart Sass version and release
  Update Dart Sass version and release
  Revert "Remove workaround for dart-lang/setup-dart#59 (sass#151)" (sass#153)
  Update Dart Sass version and release
  Update Dart Sass version and release
  Remove workaround for dart-lang/setup-dart#59 (sass#151)
  Update Dart Sass version and release
  Update Dart Sass version and release
  Fix qemu releases (sass#149)
  Update Dart Sass version and release
  Bump sass_api from 4.2.1 to 5.0.0 (sass#143)
  Bump meta from 1.8.0 to 1.9.0 (sass#144)
  Bump grinder from 0.9.2 to 0.9.3 (sass#145)
  Add missing setup-dart step in qemu release (sass#147)
  Use buf instead of protoc to compile protobufs (sass#146)
  ...

.github/util/build-protobuf/action.yml

@@ -0,0 +1,18 @@
+name: Build Protobuf
+description: Check out and build the Dart Sass embedded protocol buffer.
+inputs:
+  github-token: {required: true}
+runs:
+  using: composite
+  steps:
+    - uses: bufbuild/buf-setup-action@v1.13.1
+      with: {github_token: "${{ inputs.github-token }}"}
+
+    - name: Check out embedded Sass protocol
+      uses: sass/clone-linked-repo@v1
+      with: {repo: sass/embedded-protocol, path: build/embedded-protocol}
+
+    - name: Generate Dart from protobuf
+      run: dart run grinder protobuf
+      env: {UPDATE_SASS_PROTOCOL: false}
+      shell: bash