Add GitHub Actions CI workflow for PR testing

- Runs unit tests with pytest on Python 3.12
- Only triggers on PRs to main branch
- Includes code coverage reporting (non-blocking)
- Lint checks for code quality (non-blocking)
- Integration tests are optional and non-blocking

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

.github/workflows/test.yml

@@ -0,0 +1,80 @@
+name: Tests
+
+on:
+  pull_request:
+    branches: [ main ]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v4
+
+    - name: Set up Python 3.12
+      uses: actions/setup-python@v5
+      with:
+        python-version: "3.12"
+        cache: 'pip'
+
+    - name: Install dependencies
+      run: |
+        python -m pip install --upgrade pip
+        pip install -r requirements-dev.txt
+
+    - name: Run unit tests with coverage
+      run: |
+        pytest -v -m "not integration" --cov=nadlan_mcp --cov-report=xml --cov-report=term
+      continue-on-error: false
+
+    - name: Upload coverage to Codecov
+      uses: codecov/codecov-action@v4
+      with:
+        file: ./coverage.xml
+        flags: unittests
+        name: codecov-umbrella
+        fail_ci_if_error: false
+        token: ${{ secrets.CODECOV_TOKEN }}
+      continue-on-error: true
+
+    - name: Run integration tests (if configured)
+      run: |
+        pytest -v -m integration || echo "Integration tests skipped (requires API access)"
+      continue-on-error: true
+
+  lint:
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v4
+
+    - name: Set up Python
+      uses: actions/setup-python@v5
+      with:
+        python-version: "3.13"
+        cache: 'pip'
+
+    - name: Install dependencies
+      run: |
+        python -m pip install --upgrade pip
+        pip install -r requirements-dev.txt
+
+    - name: Run black (check only)
+      run: |
+        black --check nadlan_mcp/ tests/
+      continue-on-error: true
+
+    - name: Run isort (check only)
+      run: |
+        isort --check-only nadlan_mcp/ tests/
+      continue-on-error: true
+
+    - name: Run flake8
+      run: |
+        flake8 nadlan_mcp/ tests/ --max-line-length=120 --extend-ignore=E203,W503
+      continue-on-error: true
+
+    - name: Run mypy
+      run: |
+        mypy nadlan_mcp/ --ignore-missing-imports
+      continue-on-error: true