fix: negative perf color, parallel SP calls in chart controller, sort comment

CertReports.Syncfusion/Services/Implementations/FundDataService.cs

@@ -66,7 +66,7 @@ public class FundDataService : IFundDataService
             _logger.LogError(ex, "Errore GetChartPricesAsync per ISIN {Isin}", isin);
             throw;
         }
-        points.Sort((a, b) => a.Date.CompareTo(b.Date));
+        points.Sort((a, b) => a.Date.CompareTo(b.Date)); // defensive: SP returns ASC but enforce here
         return points;
     }