chore: add quality infra matrix, constraints, and test baseline fixes

.github/workflows/pytest.yml

@@ -0,0 +1,30 @@
+name: ci
+
+on:
+  push:
+  pull_request:
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        python-version: ["3.10", "3.11", "3.12"]
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: ${{ matrix.python-version }}
+
+      - name: Install package and test deps
+        run: |
+          python -m pip install --upgrade pip
+          pip install -c constraints.txt -e .[dev]
+
+      - name: Run tests
+        run: |
+          pytest -q