Add GitHub Actions workflow to auto-build and deploy to Pages

Builds the Docusaurus site and deploys via actions/deploy-pages on
every push to main, plus manual workflow_dispatch.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: madoiscool

.github/workflows/deploy.yml

@@ -0,0 +1,57 @@
+name: Deploy to GitHub Pages
+
+on:
+  push:
+    branches:
+      - main
+  workflow_dispatch: # Allow manual triggering
+
+# Allow GITHUB_TOKEN to deploy to GitHub Pages
+permissions:
+  contents: read
+  pages: write
+  id-token: write
+
+# Allow one concurrent deployment, cancelling in-progress runs
+concurrency:
+  group: pages
+  cancel-in-progress: false
+
+jobs:
+  build:
+    name: Build Docusaurus
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '20'
+          cache: npm
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Build website
+        run: npm run build
+
+      - name: Upload Pages artifact
+        uses: actions/upload-pages-artifact@v3
+        with:
+          path: build
+
+  deploy:
+    name: Deploy to GitHub Pages
+    needs: build
+    runs-on: ubuntu-latest
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
+    steps:
+      - name: Deploy to GitHub Pages
+        id: deployment
+        uses: actions/deploy-pages@v4