Add GH Action for automatic publishing to PyPI

Author: swainn

.github/workflows/publish.yml

@@ -0,0 +1,38 @@
+name: Publish to PyPI
+
+on:
+  push:
+    tags:
+      - '*.*.*'  # Triggers on version tags like 2.4.0, 1.0.0, etc.
+
+jobs:
+  build-and-publish:
+    runs-on: ubuntu-latest
+    permissions:
+      id-token: write  # Required for trusted publishing
+    
+    steps:
+    - uses: actions/checkout@v4
+      with:
+        fetch-depth: 0  # Fetch full history for setuptools_scm
+    
+    - name: Set up Python
+      uses: actions/setup-python@v5
+      with:
+        python-version: '3.12'
+    
+    - name: Install build dependencies
+      run: |
+        python -m pip install --upgrade pip
+        pip install build setuptools_scm[toml]
+    
+    - name: Build package
+      run: python -m build
+    
+    - name: Publish to PyPI
+      uses: pypa/gh-action-pypi-publish@release/v1
+      with:
+        # Using trusted publishing (recommended)
+        # No API token needed if trusted publishing is configured
+        # Otherwise, add PYPI_API_TOKEN to repository secrets
+        password: ${{ secrets.PYPI_API_TOKEN }}