ci: auto-create GitHub Release on tag push

- Extract changelog notes for tagged version
- Create release with .whl artifact
- Add installation instructions

Author: Detrol

.github/workflows/publish.yml

@@ -10,6 +10,7 @@ jobs:
     runs-on: ubuntu-latest
     permissions:
       id-token: write  # Required for trusted publishing
+      contents: write  # Required for creating releases
 
     steps:
       - uses: actions/checkout@v4
@@ -40,3 +41,37 @@ jobs:
 
       - name: Publish to PyPI
         uses: pypa/gh-action-pypi-publish@release/v1
+
+      - name: Extract version from tag
+        id: version
+        run: echo "VERSION=${GITHUB_REF#refs/tags/v}" >> $GITHUB_OUTPUT
+
+      - name: Extract changelog for this version
+        id: changelog
+        run: |
+          # Extract the section for this version from CHANGELOG.md
+          VERSION="${{ steps.version.outputs.VERSION }}"
+          # Get content between this version header and the next --- or ## [
+          NOTES=$(awk "/^## \[${VERSION}\]/{flag=1; next} /^---$|^## \[/{flag=0} flag" CHANGELOG.md)
+          # Handle multi-line output
+          echo "NOTES<<EOF" >> $GITHUB_OUTPUT
+          echo "$NOTES" >> $GITHUB_OUTPUT
+          echo "EOF" >> $GITHUB_OUTPUT
+
+      - name: Create GitHub Release
+        uses: softprops/action-gh-release@v2
+        with:
+          name: v${{ steps.version.outputs.VERSION }}
+          body: |
+            ## What's Changed
+
+            ${{ steps.changelog.outputs.NOTES }}
+
+            ## Installation
+
+            ```bash
+            pip install quorum-cli==${{ steps.version.outputs.VERSION }}
+            ```
+
+            See [CHANGELOG.md](https://github.com/Detrol/quorum-cli/blob/main/CHANGELOG.md) for full history.
+          files: dist/*.whl