Add CentOS Stream 9 build and test support

- tests.yml: Add test-centos-stream-9 job that builds from source and runs
  the full CI check suite (lint + C++/Python tests) in a CentOS Stream 9
  container with Python 3.11 and 3.12
- release.yml: Add test_wheels_centos_stream_9 job that downloads the
  manylinux wheels and verifies they install and import correctly on
  CentOS Stream 9; publish_pypi now depends on this validation passing

Co-authored-by: Andrey G <networmix@gmail.com>

Author: cursoragent

.github/workflows/release.yml

@@ -61,9 +61,30 @@ jobs:
           name: cibw-sdist
           path: dist/*.tar.gz
 
+  test_wheels_centos_stream_9:
+    name: Test wheels (CentOS Stream 9)
+    needs: [build_wheels]
+    runs-on: ubuntu-latest
+    container: quay.io/centos/centos:stream9
+    steps:
+      - name: Install Python
+        run: dnf install -y python3.11 python3.11-pip
+
+      - uses: actions/download-artifact@v4
+        with:
+          pattern: cibw-wheels-ubuntu-*
+          path: wheelhouse
+          merge-multiple: true
+
+      - name: Install and test wheel
+        run: |
+          python3.11 -m pip install --upgrade pip
+          python3.11 -m pip install netgraph-core --no-index --find-links wheelhouse/
+          python3.11 -c "import netgraph_core; print('CentOS Stream 9:', netgraph_core.__version__)"
+
   publish_pypi:
     name: Publish to PyPI
-    needs: [build_wheels, build_sdist]
+    needs: [build_wheels, build_sdist, test_wheels_centos_stream_9]
     runs-on: ubuntu-latest
     environment: pypi
     permissions:

.github/workflows/tests.yml

@@ -27,6 +27,34 @@ jobs:
       - name: Run CI checks (lint + C++/Python tests)
         run: make check-ci
 
+  test-centos-stream-9:
+    name: CentOS Stream 9 (py${{ matrix.python-version }})
+    runs-on: ubuntu-latest
+    container: quay.io/centos/centos:stream9
+    strategy:
+      fail-fast: false
+      matrix:
+        python-version: ["3.11", "3.12"]
+    steps:
+      - name: Install system dependencies
+        run: |
+          dnf install -y \
+            gcc gcc-c++ make cmake ninja-build git \
+            python${{ matrix.python-version }} \
+            python${{ matrix.python-version }}-devel \
+            python${{ matrix.python-version }}-pip \
+            libatomic
+
+      - uses: actions/checkout@v4
+
+      - name: Install Python deps
+        run: |
+          python${{ matrix.python-version }} -m pip install -U pip wheel
+          python${{ matrix.python-version }} -m pip install -e .[dev]
+
+      - name: Run CI checks
+        run: PYTHON=python${{ matrix.python-version }} make check-ci
+
   coverage:
     name: Coverage (ubuntu, py3.11)
     runs-on: ubuntu-22.04