Add GitHub Actions CI/CD workflows

Configure automated pipelines:
- CI workflow: lint, type check, security scan, tests
- Multi-Python version testing (3.9-3.12)
- Release workflow for PyPI publishing
- Code coverage reporting

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: cameronhopkin

.github/workflows/ci.yml

@@ -0,0 +1,82 @@
+name: CI
+
+on:
+  push:
+    branches: [main, develop]
+  pull_request:
+    branches: [main]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        python-version: ["3.9", "3.10", "3.11", "3.12"]
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Python ${{ matrix.python-version }}
+        uses: actions/setup-python@v5
+        with:
+          python-version: ${{ matrix.python-version }}
+          cache: "pip"
+
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          pip install -e ".[dev]"
+
+      - name: Run linting
+        run: |
+          ruff check src/ tests/
+          black --check src/ tests/
+
+      - name: Run type checking
+        run: |
+          mypy src/ --ignore-missing-imports
+
+      - name: Run security scan
+        run: |
+          bandit -r src/ -c pyproject.toml
+
+      - name: Run tests
+        run: |
+          pytest --cov=cmmc_validator --cov-report=xml --cov-report=term-missing
+
+      - name: Upload coverage
+        uses: codecov/codecov-action@v4
+        if: matrix.python-version == '3.11'
+        with:
+          file: ./coverage.xml
+          fail_ci_if_error: false
+
+  build:
+    runs-on: ubuntu-latest
+    needs: test
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: "3.11"
+
+      - name: Install build tools
+        run: |
+          python -m pip install --upgrade pip
+          pip install build twine
+
+      - name: Build package
+        run: python -m build
+
+      - name: Check package
+        run: twine check dist/*
+
+      - name: Upload artifacts
+        uses: actions/upload-artifact@v4
+        with:
+          name: dist
+          path: dist/

.github/workflows/release.yml

@@ -0,0 +1,31 @@
+name: Release
+
+on:
+  release:
+    types: [published]
+
+jobs:
+  publish:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: "3.11"
+
+      - name: Install build tools
+        run: |
+          python -m pip install --upgrade pip
+          pip install build twine
+
+      - name: Build package
+        run: python -m build
+
+      - name: Publish to PyPI
+        env:
+          TWINE_USERNAME: __token__
+          TWINE_PASSWORD: ${{ secrets.PYPI_API_TOKEN }}
+        run: twine upload dist/*