Add GitHub Pages website and deploy CI

Author: lemire

.github/workflows/pages.yml

@@ -0,0 +1,37 @@
+name: Deploy GitHub Pages
+
+# Publishes the static site in website/ to the gh-pages branch
+# whenever the website (or this workflow) changes on master.
+
+on:
+  push:
+    branches: [master]
+    paths:
+      - 'website/**'
+      - '.github/workflows/pages.yml'
+  workflow_dispatch:
+
+permissions:
+  contents: write
+
+concurrency:
+  group: pages-deploy
+  cancel-in-progress: true
+
+jobs:
+  deploy:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Publish website/ to gh-pages
+        uses: peaceiris/actions-gh-pages@v4
+        with:
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+          publish_dir: ./website
+          publish_branch: gh-pages
+          # keep_files is false: gh-pages will mirror website/ exactly
+          user_name: 'github-actions[bot]'
+          user_email: 'github-actions[bot]@users.noreply.github.com'
+          commit_message: 'Deploy website from ${{ github.sha }}'