rely on actions/deploy-pages in deploy job to do without paasapcom user

.github/workflows/deploy-manual.yml

@@ -23,11 +23,13 @@ jobs:
       VALIDATOR_OAUTH_CLIENT_ID: ${{ secrets.VALIDATOR_OAUTH_CLIENT_ID }}
       VALIDATOR_OAUTH_CLIENT_SECRET: ${{ secrets.VALIDATOR_OAUTH_CLIENT_SECRET }}
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
         with:
+          # fetch complete history for step "export drawios" to safely determine
+          # date of last update to drawio files via git log
           fetch-depth: 0
 
-      - uses: actions/setup-node@v4
+      - uses: actions/setup-node@v6
         with:
           node-version: '24'
           cache: npm
@@ -76,66 +78,19 @@ jobs:
         run: node src/_scripts/_update-drawio-links.js
 
       - name: Upload Build Artifact
-        uses: actions/upload-pages-artifact@v3
+        uses: actions/upload-pages-artifact@v5
         with:
           path: build
 
   deploy:
     name: Deploy Site
     runs-on: ubuntu-latest
     needs: build
-    environment: github-pages
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
     if: success()
     steps:
-      - name: Checkout Repository
-        uses: actions/checkout@v4
-        with:
-          fetch-depth: 0
-          token: ${{ secrets.PAASAPCOM_PAT }}
-
-      - name: Download Build Artifact
-        uses: actions/download-artifact@v4
-        with:
-          path: __build__
-
-      - name: Set up Git
-        run: |
-          git config --global user.email "paa@sap.com"
-          git config --global user.name "paasapcom"
-
-      - name: Switch to Pages Branch
-        run: |
-          gh_pages_branch=$(gh api "repos/$GITHUB_REPOSITORY/pages" --jq '.source.branch')
-          git fetch origin $gh_pages_branch
-          git checkout $gh_pages_branch
-          echo "gh_pages_branch=$gh_pages_branch" >> "$GITHUB_ENV"
-        env:
-          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-
-      - name: Drop Previous Content
-        run: |
-          shopt -s extglob
-          rm -rf !(@*|__build__)
-
-      - name: Extract Build Content
-        run: |
-          if [[ -d "__build__" && "$(ls -A __build__)" ]]; then
-            mv __build__/* ./
-            tar -xvf github-pages/artifact.tar
-            rm github-pages/artifact.tar
-            rm -rf __build__
-          else
-            echo "No build files found. Skipping move step."
-          fi
-
-      - name: Commit and Push Changes
-        env:
-          GITHUB_TOKEN: ${{ secrets.PAASAPCOM_PAT }}
-        # prevent history build-up and .git bloat with orphan
-        run: |
-          git checkout --orphan site-anew
-          git add -A
-          if [[ "$(git status -s)" ]]; then
-            git commit -m "site build ➝ gh pages"
-            git push -f origin HEAD:${{ env.gh_pages_branch }}
-          fi
+      - name: Deploy to GitHub Pages
+        id: deployment
+        uses: actions/deploy-pages@v5