Add Azure Service Bus integration toggle

Introduced a new configuration constant `useAzureServiceBus` to control the optional integration with Azure Service Bus. Implemented conditional logic to bind Azure Service Bus options from configuration if the flag is enabled.

src/bundles/Elsa.Server.Web/Program.cs

@@ -49,6 +49,7 @@
 const bool useCaching = true;
 const bool useReadOnlyMode = false;
 const bool useSignalR = true;
+const bool useAzureServiceBus = false;
 const DistributedCachingTransport distributedCachingTransport = DistributedCachingTransport.MassTransit;
 const MassTransitBroker useMassTransitBroker = MassTransitBroker.AzureServiceBus;
 
@@ -328,6 +329,9 @@
             elsa.UseRealTimeWorkflows();
         }
 
+        if (useAzureServiceBus)
+            elsa.UseAzureServiceBus(asb => asb.AzureServiceBusOptions += options => configuration.GetSection("AzureServiceBus").Bind(options));
+
         if (useMassTransit)
         {
             elsa.UseMassTransit(massTransit =>