Uploads the merged coverage data too

.github/workflows/ci.yml

@@ -377,6 +377,15 @@ jobs:
           mkdir -p .nyc_output
           npx nyc merge coverage .nyc_output/out.json
           npx nyc report --reporter=lcovonly --report-dir coverage
+      - name: Upload coverage artifacts
+        uses: actions/upload-artifact@v4
+        with:
+          name: merged-coverage
+          path: |
+            merged-backend-coverage.xml
+            .nyc_output/
+          retention-days: 7
+          if-no-files-found: error
       - name: SonarQube Analysis
         uses: SonarSource/sonarqube-scan-action@v5
         env: