fix: register DatadogTransactionTracker and IHttpClientFactory in AWS adapter

Without these registrations, resolving AcknowledgePrintJobCommandHandler in
DRIVEN=AWS deployments failed with an unresolved-service exception. Also adds
Activity span tagging for dsm.transaction_id and dsm.transaction.checkpoint
in both Core and Client transaction trackers.

Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>

Author: jeastham1993

print-service/src/Stickerlandia.PrintService.AWS/ServiceExtensions.cs

@@ -16,6 +16,7 @@
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.DependencyInjection;
 using Stickerlandia.PrintService.Core;
+using Stickerlandia.PrintService.Core.Observability;
 using Stickerlandia.PrintService.Core.Outbox;
 using Stickerlandia.PrintService.Core.PrintJobs;
 
@@ -61,6 +62,9 @@ public static IServiceCollection AddAwsAdapters(this IServiceCollection services
 
         services.AddSingleton<IPrintServiceEventPublisher, EventBridgeEventPublisher>();
 
+        services.AddHttpClient();
+        services.AddSingleton<DatadogTransactionTracker>();
+
         return services;
     }
 }

print-service/src/Stickerlandia.PrintService.Client/Telemetry/DatadogTransactionTracker.cs

@@ -4,6 +4,7 @@
 
 #pragma warning disable
 
+using System.Diagnostics;
 using System.Globalization;
 using System.IO.Compression;
 using System.Net.Http.Headers;
@@ -47,6 +48,12 @@ internal async Task TrackTransactionAsync(string transactionId, string checkpoin
 
         try
         {
+            if (Activity.Current is not null)
+            {
+                Activity.Current.SetTag("dsm.transaction_id", transactionId);
+                Activity.Current.SetTag("dsm.transaction.checkpoint", checkpoint);
+            }
+            
             var timestampNanos = (DateTimeOffset.UtcNow.ToUnixTimeMilliseconds() * 1_000_000L)
                 .ToString(CultureInfo.InvariantCulture);
 

print-service/src/Stickerlandia.PrintService.Core/Observability/DatadogTransactionTracker.cs

@@ -2,6 +2,7 @@
 // This product includes software developed at Datadog (https://www.datadoghq.com/).
 // Copyright 2026 Datadog, Inc.
 
+using System.Diagnostics;
 using System.Globalization;
 using System.IO.Compression;
 using System.Net.Http.Headers;
@@ -47,6 +48,12 @@ public async Task TrackTransactionAsync(string transactionId, string checkpoint)
 
         try
         {
+            if (Activity.Current is not null)
+            {
+                Activity.Current.SetTag("dsm.transaction_id", transactionId);
+                Activity.Current.SetTag("dsm.transaction.checkpoint", checkpoint);
+            }
+            
             var timestampNanos = (DateTimeOffset.UtcNow.ToUnixTimeMilliseconds() * 1_000_000L)
                 .ToString(CultureInfo.InvariantCulture);