chore: Add prettier.

.editorconfig

@@ -13,6 +13,12 @@ insert_final_newline = true
 trim_trailing_whitespace = true
 indent_style = space
 indent_size = 4
+max_line_length = 120
 
-[*.{json,json.dist,yml,yml.dist}]
-indent_size = 4
+[*.{json,json.dist,yml,yaml,yml.dist,yaml.dist}]
+indent_size = 4
+max_line_length = 120
+
+[*.{md}]
+indent_size = 2
+max_line_length = 80

.github/workflows/prettier.yml

@@ -0,0 +1,22 @@
+name: Prettier checks
+
+# This action works with pull requests and pushes
+on:
+    pull_request:
+    push:
+        branches:
+            - master
+
+jobs:
+    prettier:
+        runs-on: ubuntu-latest
+
+        steps:
+            - name: Checkout
+              uses: actions/checkout@v3
+
+            - name: Install the Nix package manager
+              uses: cachix/install-nix-action@v17
+
+            - name: Checks
+              run: nix run nixpkgs#nodePackages.prettier -- --check .

.prettierignore

@@ -0,0 +1,6 @@
+/.direnv/
+/.idea/
+/build/
+/vendor/
+/docs/
+CHANGELOG.md