ci: switch deployment from GitHub Actions Pages API to gh-pages branch

Replace actions/upload-pages-artifact + actions/deploy-pages with
peaceiris/actions-gh-pages@v4. The build artifacts (final-site/) are
now pushed to the gh-pages branch instead of being deployed via the
GitHub Pages workflow API.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: InfoTech.io Bot

.github/workflows/deploy-github-pages.yml

@@ -22,9 +22,7 @@ on:
         default: false
 
 permissions:
-  contents: read
-  pages: write
-  id-token: write
+  contents: write
 
 # Single concurrency group ensures atomic deployments
 concurrency:
@@ -34,9 +32,6 @@ concurrency:
 jobs:
   deploy:
     runs-on: ubuntu-latest
-    environment:
-      name: github-pages
-      url: ${{ steps.deployment.outputs.page_url }}
 
     steps:
       # ==========================================
@@ -327,21 +322,19 @@ jobs:
           echo "✅ Verification complete"
 
       # ==========================================
-      # PHASE 7: Atomic Deployment
+      # PHASE 7: Deploy to gh-pages branch
       # ==========================================
-      - name: Upload Pages Artifact
-        uses: actions/upload-pages-artifact@v3
+      - name: Deploy to gh-pages branch
+        uses: peaceiris/actions-gh-pages@v4
         with:
-          path: final-site
-
-      - name: Deploy to GitHub Pages
-        id: deployment
-        uses: actions/deploy-pages@v4
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+          publish_dir: ./final-site
+          publish_branch: gh-pages
 
       - name: Deployment Success
         run: |
           echo "✅ GitHub Pages federation deployed successfully!"
-          echo "🌐 URL: ${{ steps.deployment.outputs.page_url }}"
+          echo "🌐 URL: https://info-tech-io.github.io"
           echo ""
           echo "📋 Deployment Summary:"
           echo "  - Corporate site: Updated ✅"