chore: add formatting and CI checks

Author: softpudding

.github/CONTRIBUTING.md

@@ -67,10 +67,13 @@ When you open a Pull Request, the CLA Assistant bot will automatically check if
 3. Install dependencies:
    ```bash
    # Python dependencies
-   uv sync
+   uv sync --extra dev
 
    # Extension dependencies
    cd extension && npm install && cd ..
+
+   # Install git hooks
+   uv run pre-commit install
    ```
 
 ## Development Setup
@@ -79,11 +82,14 @@ When you open a Pull Request, the CLA Assistant bot will automatically check if
 
 ```bash
 # Install with dev dependencies
-uv sync --group dev
+uv sync --extra dev
 
 # Run the server
 uv run local-chrome-server serve
 
+# Run pre-commit checks
+uv run pre-commit run --all-files
+
 # Run tests
 uv run pytest
 
@@ -105,8 +111,17 @@ npm run dev
 # Production build
 npm run build
 
+# Format
+npm run format
+
+# Lint
+npm run lint
+
 # Type checking
 npm run typecheck
+
+# Tests
+npm test
 ```
 
 ## Pull Request Process
@@ -119,6 +134,7 @@ npm run typecheck
 2. **Make your changes** following our coding standards
 
 3. **Test your changes**:
+   - Run `uv run pre-commit run --all-files`
    - Run the test suite
    - Test manually if applicable
    - Check type errors
@@ -148,7 +164,7 @@ npm run typecheck
 - **Line length**: 88 characters (black/ruff)
 - **Target**: Python 3.12+
 - **Type hints**: Required (strict mypy)
-- **Formatting**: Use ruff for linting and formatting
+- **Formatting**: Use black for formatting and ruff for linting/import sorting
 - **Imports**: Sorted via ruff (isort compatible)
 
 ### TypeScript
@@ -157,6 +173,7 @@ npm run typecheck
 - **Strict mode**: Enabled
 - **Path alias**: Use `@/*` for `src/*`
 - **No type suppression**: Avoid `as any`, `@ts-ignore`, `@ts-expect-error`
+- **Formatting/Linting**: Use Prettier and ESLint before committing
 
 ### General
 
@@ -172,4 +189,4 @@ npm run typecheck
 
 ---
 
-Thank you for contributing to OpenBrowser!
+Thank you for contributing to OpenBrowser!

.github/workflows/ci.yml

@@ -0,0 +1,112 @@
+name: CI
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+jobs:
+  pre-commit:
+    name: Pre-commit
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Check out code
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.12'
+
+      - name: Set up uv
+        uses: astral-sh/setup-uv@v5
+
+      - name: Set up Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '22'
+          cache: npm
+          cache-dependency-path: extension/package-lock.json
+
+      - name: Install Python dependencies
+        run: uv sync --extra dev
+
+      - name: Install extension dependencies
+        working-directory: extension
+        run: npm ci
+
+      - name: Run pre-commit
+        shell: bash
+        run: |
+          if [[ "${{ github.event_name }}" == "pull_request" ]]; then
+            base_sha="${{ github.event.pull_request.base.sha }}"
+          else
+            base_sha="${{ github.event.before }}"
+          fi
+
+          if [[ -z "${base_sha}" || "${base_sha}" == "0000000000000000000000000000000000000000" ]]; then
+            mapfile -t changed_files < <(git ls-files)
+          else
+            mapfile -t changed_files < <(git diff --name-only --diff-filter=ACMRTUXB "${base_sha}" "${{ github.sha }}")
+          fi
+
+          if [[ ${#changed_files[@]} -eq 0 ]]; then
+            echo "No changed files to check."
+            exit 0
+          fi
+
+          uv run pre-commit run --show-diff-on-failure --files "${changed_files[@]}"
+
+  pytest:
+    name: Pytest
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Check out code
+        uses: actions/checkout@v4
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.12'
+
+      - name: Set up uv
+        uses: astral-sh/setup-uv@v5
+
+      - name: Install Python dependencies
+        run: uv sync --extra dev
+
+      - name: Run pytest
+        run: uv run pytest
+
+  extension:
+    name: Extension Tests
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Check out code
+        uses: actions/checkout@v4
+
+      - name: Set up Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '22'
+          cache: npm
+          cache-dependency-path: extension/package-lock.json
+
+      - name: Set up Bun
+        uses: oven-sh/setup-bun@v2
+        with:
+          bun-version: '1.3.11'
+
+      - name: Install extension dependencies
+        working-directory: extension
+        run: npm ci
+
+      - name: Run extension tests
+        working-directory: extension
+        run: npm test

.pre-commit-config.yaml

@@ -0,0 +1,29 @@
+repos:
+  - repo: https://github.com/pre-commit/pre-commit-hooks
+    rev: v5.0.0
+    hooks:
+      - id: check-toml
+        files: ^pyproject\.toml$
+      - id: check-yaml
+        files: ^(\.pre-commit-config\.yaml|\.github/workflows/.*\.ya?ml)$
+
+  - repo: local
+    hooks:
+      - id: black
+        name: black
+        entry: uv run black
+        language: system
+        types_or: [python, pyi]
+        require_serial: true
+
+      - id: extension-prettier
+        name: extension prettier
+        entry: npm --prefix extension exec prettier -- --write --ignore-unknown
+        language: system
+        files: ^extension/(?!package-lock\.json$).*\.(ts|tsx|js|mjs|cjs|json|html|css|md)$
+
+      - id: extension-eslint
+        name: extension eslint
+        entry: npm --prefix extension exec eslint -- --config extension/eslint.config.mjs --max-warnings=0
+        language: system
+        files: ^extension/.*\.ts$