Add CI workflow with ruff linting and multi-version testing

Author: kwent

.github/workflows/ci.yml

@@ -0,0 +1,52 @@
+name: CI
+
+on:
+  push:
+    branches: [master]
+  pull_request:
+    branches: [master]
+
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v6
+
+      - name: Set up Python
+        uses: actions/setup-python@v6
+        with:
+          python-version: '3.12'
+
+      - name: Install uv
+        run: pip install uv
+
+      - name: Install dependencies
+        run: uv pip install --system ruff
+
+      - name: Ruff check
+        run: ruff check .
+
+      - name: Ruff format check
+        run: ruff format --check .
+
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        python-version: ['3.10', '3.11', '3.12']
+    steps:
+      - uses: actions/checkout@v6
+
+      - name: Set up Python ${{ matrix.python-version }}
+        uses: actions/setup-python@v6
+        with:
+          python-version: ${{ matrix.python-version }}
+
+      - name: Install uv
+        run: pip install uv
+
+      - name: Install package
+        run: uv pip install --system .
+
+      - name: Test SDK imports
+        run: python -c "import rootly_sdk; print('SDK imports successfully')"