ci: add GitHub Actions workflow (library + dev jobs)

.github/workflows/ci.yml

@@ -0,0 +1,37 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+jobs:
+  library:
+    name: Library tests (no torch)
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, windows-latest]
+        python: ["3.12", "3.13"]
+    steps:
+      - uses: actions/checkout@v4
+      - uses: astral-sh/setup-uv@v3
+      - run: uv venv --python ${{ matrix.python }}
+      - run: uv pip install -e . pytest
+      - run: uv run pytest tests/unit -v
+
+  dev:
+    name: Full dev suite (with torch)
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, windows-latest]
+        python: ["3.12", "3.13"]
+    steps:
+      - uses: actions/checkout@v4
+      - uses: astral-sh/setup-uv@v3
+      - run: uv sync --group dev --python ${{ matrix.python }}
+      - run: uv run pytest tests/ -v