Fix: Implement FixPlan part A9, A10, B

src/Predictalytics.Worker/Services/TradeContextEnrichmentWorker.cs

@@ -107,6 +107,11 @@ public class TradeContextEnrichmentWorker : BackgroundService
                             updatedCount++;
                         }
                     }
+                    catch (OperationCanceledException) when (stoppingToken.IsCancellationRequested)
+                    {
+                        _logger.LogInformation("Cancellation requested during enrichment, stopping batch.");
+                        break;
+                    }
                     catch (Exception ex)
                     {
                         _logger.LogError(ex, "Failed to enrich asset {AssetId}", assetId);