fix(ci): match both Cobertura.xml and coverage.cobertura.xml in merge-coverage

The macOS build uploads reportgenerator output (Cobertura.xml) while
merge-coverage searched only for coverlet raw output (coverage.cobertura.xml).
Expand the glob to match both naming conventions and add continue-on-error
to update-badges download steps for resilience.

Made-with: Cursor

Author: Hongwei-MB

.github/workflows/ci.yml

@@ -396,7 +396,7 @@ jobs:
         run: |
           dotnet tool restore
           shopt -s nullglob globstar
-          REPORTS=(artifacts/coverage-reports/**/coverage.cobertura.xml)
+          REPORTS=(artifacts/coverage-reports/**/coverage.cobertura.xml artifacts/coverage-reports/**/Cobertura.xml)
           if [ ${#REPORTS[@]} -eq 0 ]; then
             echo "No coverage reports found — skipping merge."
             exit 0
@@ -432,12 +432,14 @@ jobs:
       - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
 
       - name: Download coverage report
+        continue-on-error: true
         uses: actions/download-artifact@3e5f45b2cfb9172054b4087a40e8e0b5a5461e7c # v8.0.1
         with:
           name: merged-coverage-report
           path: coverage-report
 
       - name: Download test results
+        continue-on-error: true
         uses: actions/download-artifact@3e5f45b2cfb9172054b4087a40e8e0b5a5461e7c # v8.0.1
         with:
           name: test-results-macos