Add GitHub Actions workflow for publishing to TestPyPI and PyPI

.github/workflows/publish.yml

@@ -0,0 +1,43 @@
+name: Publish
+
+on:
+  push:
+    branches:
+      - main
+      - staging
+  workflow_dispatch:
+
+jobs:
+  build-and-publish:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v5
+
+      - name: Set up Python
+        uses: actions/setup-python@v6
+        with:
+          python-version: "3.12"
+
+      - name: Install uv
+        uses: astral-sh/setup-uv@v3
+
+      - name: Build distributions
+        run: |
+          rm -rf dist
+          uv build
+
+      - name: Publish to TestPyPI
+        if: github.ref == 'refs/heads/staging'
+        uses: pypa/gh-action-pypi-publish@release/v1
+        with:
+          user: __token__
+          password: ${{ secrets.TEST_PYPI_API_TOKEN }}
+          repository-url: https://test.pypi.org/legacy/
+
+      - name: Publish to PyPI
+        if: github.ref == 'refs/heads/main'
+        uses: pypa/gh-action-pypi-publish@release/v1
+        with:
+          user: __token__
+          password: ${{ secrets.PYPI_API_TOKEN }}