Add GitHub Actions workflow for Zola deployment

- Automated deployment to GitHub Pages on main branch pushes
- Build validation on pull requests
- Uses Zola 0.19.1 for consistent builds
- Includes link checking and proper Pages deployment

Author: Anne-Julia Seitz

.github/workflows/deploy.yml

@@ -0,0 +1,60 @@
+name: Deploy Zola site to GitHub Pages
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    if: github.ref != 'refs/heads/main'
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        
+      - name: Setup Zola
+        uses: taiki-e/install-action@v2
+        with:
+          tool: [email protected]
+          
+      - name: Build site
+        run: zola build
+        
+      - name: Check internal links
+        run: zola check
+
+  deploy:
+    runs-on: ubuntu-latest
+    if: github.ref == 'refs/heads/main'
+    permissions:
+      contents: read
+      pages: write
+      id-token: write
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        
+      - name: Setup Zola
+        uses: taiki-e/install-action@v2
+        with:
+          tool: [email protected]
+          
+      - name: Build site
+        run: zola build
+        
+      - name: Setup Pages
+        uses: actions/configure-pages@v4
+        
+      - name: Upload artifact
+        uses: actions/upload-pages-artifact@v3
+        with:
+          path: ./public
+          
+      - name: Deploy to GitHub Pages
+        id: deployment
+        uses: actions/deploy-pages@v4