Add dependabot and a simple build/publish workflow

.github/dependabot.yml

@@ -0,0 +1,12 @@
+version: 2
+updates:
+# Maintain dependencies for GitHub Actions
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+    # Open update PRs in groups rather than one-by-one
+    groups:
+      actions:
+        patterns:
+          - "*"

.github/workflows/publish.yml

@@ -0,0 +1,55 @@
+name: Build and upload to PyPI
+
+on:
+  # Allow manual triggering of the workflow, but note that the upload
+  # to PyPI step will not run manual trigger.
+  workflow_dispatch:
+  # Run workflow on pullrequests, but note that the upload to PyPI step
+  # will not run on pull requests.
+  pull_request:
+  # Run workflow on push to main branch, but note that the upload to
+  # PyPI step will not run on pushes. We could change that if we wanted
+  # to have it publish on tags -- see the upload_pypi job below.
+  push:
+    branches:
+      - main
+  # Run workflow on GitHub release done through the UI -- this is the only
+  # time the upload to PyPI step will run.
+  release:
+    types:
+      - published
+
+jobs:
+  build_wheel_sdist:
+    name: Build wheel and sdist
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Build wheel and sdist
+        run: pipx run build
+
+      - uses: actions/upload-artifact@v4
+        with:
+          name: wheel-sdist
+          path: dist/*
+
+  upload_pypi:
+    needs: [build_wheel_sdist]
+    runs-on: ubuntu-latest
+    environment: publish
+    permissions:
+      id-token: write
+    if: github.event_name == 'release' && github.event.action == 'published'
+    # or, alternatively, upload to PyPI on every tag starting with 'v' (remove on: release above to use this)
+    # if: github.event_name == 'push' && startsWith(github.ref, 'refs/tags/v')
+    steps:
+      - uses: actions/download-artifact@v4
+        with:
+          # unpacks all CIBW artifacts into dist/
+          pattern: wheel-sdist
+          path: dist
+          merge-multiple: true
+
+      - uses: pypa/gh-action-pypi-publish@release/v1