ci: add automatic GitHub Release creation

Author: tanbro

.github/workflows/ci.yml

@@ -10,7 +10,7 @@ on:
     branches: [main]
 
 permissions:
-  contents: read
+  contents: write # Required for GitHub Release creation
   id-token: write # Required for Trusted Publishing (only used in publish job)
 
 jobs:
@@ -144,3 +144,44 @@ jobs:
         with:
           skip-existing: true
           verbose: true
+
+  github-release:
+    name: Create GitHub Release
+    runs-on: ubuntu-latest
+    needs: [validate-tag, build]
+    if: needs.validate-tag.outputs.version != ''
+    permissions:
+      contents: write
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Download distribution packages
+        uses: actions/download-artifact@v7
+        with:
+          name: python-package-distributions
+          path: dist/
+
+      - name: Generate release notes from CHANGELOG
+        id: release_notes
+        run: |
+          VERSION="${{ needs.validate-tag.outputs.version }}"
+          awk -v version="$VERSION" '
+            /^##[[:space:]]*$version/ { in_release=1; next }
+            in_release && /^##[[:space:]]/ { exit }
+            in_release { print }
+          ' CHANGELOG.md > release_notes.md
+          echo "notes<<$EOF" >> $GITHUB_OUTPUT
+          cat release_notes.md >> $GITHUB_OUTPUT
+          echo "$EOF" >> $GITHUB_OUTPUT
+
+      - name: Create GitHub Release
+        uses: softprops/action-gh-release@v2
+        with:
+          tag_name: ${{ github.ref }}
+          name: v${{ needs.validate-tag.outputs.version }}
+          body: ${{ steps.release_notes.outputs.notes }}
+          files: dist/*
+          generate_release_notes: false
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}