ci: add release workflow for GitHub Releases

Creates GitHub release on tag push. Runs tests before releasing.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: jgamblin

.github/workflows/release.yml

@@ -0,0 +1,20 @@
+name: Release
+
+on:
+  push:
+    tags: ["v*"]
+
+jobs:
+  release:
+    runs-on: macos-14
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-python@v5
+        with:
+          python-version: "3.12"
+      - run: pip install -e ".[dev]"
+      - run: pytest tests/ -v
+      - name: Create GitHub Release
+        uses: softprops/action-gh-release@v2
+        with:
+          generate_release_notes: true