Restructure workflow to match official Vite documentation

Based on official Vite docs and working examples, restructured workflow to:
- Use single deploy job instead of separate build/deploy jobs
- Add missing actions/configure-pages@v5 step
- Upgrade to Node 20 LTS
- Use npm ci as recommended
- Update to latest action versions

This matches the proven pattern from vite.dev/guide/static-deploy

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

Author: jsfledd

.github/workflows/deploy.yml

@@ -12,46 +12,39 @@ permissions:
   id-token: write
 
 concurrency:
-  group: "pages"
-  cancel-in-progress: false
+  group: 'pages'
+  cancel-in-progress: true
 
 jobs:
-  build:
+  deploy:
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
         uses: actions/checkout@v4
 
-      - name: Setup Node
+      - name: Set up Node
         uses: actions/setup-node@v4
         with:
-          node-version: '18'
+          node-version: '20'
           cache: 'npm'
 
       - name: Install dependencies
-        run: npm install
-
-      - name: Verify vite installation
-        run: |
-          echo "Checking for vite..."
-          ls -la node_modules/vite/bin/ || echo "vite bin directory not found"
-          test -f node_modules/vite/bin/vite.js && echo "vite.js exists" || echo "vite.js NOT found"
+        run: npm ci
 
       - name: Build
-        run: npx --yes vite build
+        run: npm run build:ci
+
+      - name: Setup Pages
+        uses: actions/configure-pages@v5
 
       - name: Upload artifact
-        uses: actions/upload-pages-artifact@v3
+        uses: actions/upload-pages-artifact@v4
         with:
-          path: ./dist
+          path: './dist'
 
-  deploy:
-    environment:
-      name: github-pages
-      url: ${{ steps.deployment.outputs.page_url }}
-    runs-on: ubuntu-latest
-    needs: build
-    steps:
       - name: Deploy to GitHub Pages
         id: deployment
         uses: actions/deploy-pages@v4