Upload staged website tree for non-production runs.

Receipt-only upload-artifact for Advisor-blocked staged receipts; production path unchanged.

Co-Authored-By: Muse Spark 1.3 <noreply@opencode.ai>

Author: emcd

.github/workflows/xrepo--documenter.yaml

@@ -118,6 +118,13 @@ jobs:
         with:
           path: '${{ steps.update-website.outputs.website }}'
 
+      - name: Upload Staged Receipts
+        if: ${{ inputs.production != true }}
+        uses: actions/upload-artifact@v7
+        with:
+          name: website-staging--${{ github.run_id }}
+          path: '${{ steps.update-website.outputs.website }}'
+
   publish:
     if: startsWith(github.ref, 'refs/tags/')
     needs: generate