Restore complete Python CI matrix

Author: OVVO-Financial

.github/workflows/native-backend-ci.yml

@@ -5,23 +5,61 @@ on:
   push:
 
 jobs:
-  vignette-diagnostic:
-    name: Vignette diagnostic
+  native-backend:
+    name: Python ${{ matrix.python-version }}
     runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        python-version: ["3.11", "3.12", "3.13", "3.14"]
+
     steps:
       - name: Check out repo
         uses: actions/checkout@v4
 
       - name: Set up Python
         uses: actions/setup-python@v5
         with:
-          python-version: "3.11"
+          python-version: ${{ matrix.python-version }}
+
+      - name: Install build tools
+        run: |
+          python -m pip install -U pip
+          # numpy pinned <2.5: the R parity cache keys hash test inputs generated via
+          # multivariate_normal (LAPACK SVD). numpy 2.5.x bundles an OpenBLAS whose SVD
+          # kernels differ on some runner CPUs, changing inputs bit-for-bit and causing
+          # cache misses. Re-evaluate at the next full live-R cache regeneration.
+          python -m pip install build scikit-build-core nanobind pytest ruff mypy "numpy<2.5" scipy
+          python -m pip install hypothesis pytest-benchmark pytest-xdist
+
+      - name: Install package editable
+        run: python -m pip install -e .
+
+      - name: Run native import smoke test
+        run: python -c "import nns._nnscore as c; print(c.lpm(2.0, 0.0, [-2.0, -1.0, 0.5, 3.0]))"
 
-      - name: Install dependencies
+      - name: Run invariants without Rscript
+        run: python -m pytest -q tests/invariants
+
+      - name: Run parity from committed R cache
+        run: NNS_R_CACHE_ONLY=1 python -m pytest -q tests/parity
+
+      - name: Run plotting color-fidelity tests
+        run: python -m pytest -q tests/plotting
+
+      - name: Run vignette examples
         run: |
-          python -m pip install -q -U pip
-          python -m pip install -q build scikit-build-core nanobind pytest "numpy<2.5" scipy matplotlib hypothesis pytest-benchmark pytest-xdist
-          python -m pip install -q -e .
+          if [ -f tests/docs/test_vignette_examples.py ]; then
+            python -m pytest -q tests/docs/test_vignette_examples.py
+          else
+            echo "No docs vignette test present; skipping."
+          fi
+
+      - name: Run ruff
+        run: ruff check .
+
+      - name: Run mypy
+        run: mypy
 
-      - name: Run vignette examples with full tracebacks
-        run: python -m pytest -vv -s tests/docs/test_vignette_examples.py
+      - name: Build distributions
+        run: python -m build