chore: add Biome code quality checks

.editorconfig

@@ -0,0 +1,12 @@
+root = true
+
+[*]
+charset = utf-8
+end_of_line = lf
+insert_final_newline = true
+indent_style = space
+indent_size = 4
+trim_trailing_whitespace = true
+
+[*.md]
+trim_trailing_whitespace = false

.gitattributes

@@ -0,0 +1,19 @@
+* text=auto eol=lf
+
+*.bat text eol=crlf
+*.cmd text eol=crlf
+*.ps1 text eol=crlf
+
+*.ico binary
+*.png binary
+*.jpg binary
+*.jpeg binary
+*.gif binary
+*.webp binary
+*.woff binary
+*.woff2 binary
+*.ttf binary
+*.pyd binary
+*.dll binary
+*.exe binary
+*.zip binary

.github/workflows/quality.yml

@@ -0,0 +1,42 @@
+name: Code Quality
+
+on:
+  pull_request:
+  push:
+    branches:
+      - main
+      - master
+
+concurrency:
+  group: quality-${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+permissions:
+  contents: read
+
+jobs:
+  biome:
+    name: Biome
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: 22
+          cache: npm
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Check pull request changes
+        if: github.event_name == 'pull_request'
+        run: npm run check -- --changed --since=${{ github.event.pull_request.base.sha }} --no-errors-on-unmatched --reporter=github
+
+      - name: Check repository
+        if: github.event_name == 'push'
+        run: npm run check -- --reporter=github

README.md

@@ -44,7 +44,13 @@ git clone https://github.com/cdmtn-dev/codemotion-ide.git
 cd codemotion-ide
 
 # Install dependencies
-npm install
+npm ci
+
+# Check formatting and linting
+npm run check
+
+# Apply safe automatic fixes
+npm run check:fix
 
 # Start the development server
 npm start
@@ -77,6 +83,8 @@ We love contributions! Whether it's bug reports, feature requests, or pull reque
 #### Contributing Guidelines
 - Fork the repository
 - Create your feature branch ```git checkout -b feature/AmazingFeature```
+- Install exact dependencies with ```npm ci```
+- Run ```npm run check:fix``` before committing; ```npm run check``` is required in pull requests and reports legacy lint findings without blocking formatting checks
 - Commit your changes ```git commit -m 'Add some AmazingFeature'```
 - Push to the branch ```git push origin feature/AmazingFeature```
 - Open a Pull Request