chore: add GitHub Actions workflow for automated release and npm publishing

.github/workflows/release.yml

@@ -0,0 +1,57 @@
+name: Release
+
+on:
+  push:
+    branches:
+      - main
+  workflow_dispatch:
+    inputs:
+      publish-only:
+        description: "Skip release-please and just publish to npm (use after a failed publish)"
+        type: boolean
+        default: false
+
+concurrency:
+  group: release
+  cancel-in-progress: false
+
+jobs:
+  release-please:
+    if: ${{ !inputs.publish-only }}
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+      pull-requests: write
+      issues: write
+    outputs:
+      release_created: ${{ steps.release.outputs.release_created }}
+    steps:
+      - uses: googleapis/release-please-action@v4
+        id: release
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+
+  publish-npm:
+    needs: release-please
+    if: ${{ always() && (needs.release-please.outputs.release_created == 'true' || inputs.publish-only) }}
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      id-token: write
+    steps:
+      - uses: actions/checkout@v6
+        with:
+          ref: main
+
+      - uses: actions/setup-node@v6
+        with:
+          node-version: "20"
+          registry-url: "https://registry.npmjs.org"
+
+      - run: npm ci
+
+      - run: npm run build
+
+      - run: npm publish --access public --provenance
+        env:
+          NODE_AUTH_TOKEN: ${{ secrets.NPM_TOKEN }}