Convert document ids.

backend/src/Migrations/Migrations/MongoDb/AddAppIdToEventStream.cs

@@ -53,6 +53,8 @@ namespace Migrations.Migrations.MongoDb
                     var eventStream = document["EventStream"].AsString;
 
                     if (TryGetAppId(document, out var appId))
+                    {
+                        if (!eventStream.StartsWith("app-", StringComparison.OrdinalIgnoreCase))
                         {
                             var indexOfType = eventStream.IndexOf('-');
                             var indexOfId = indexOfType + 1;
@@ -67,8 +69,6 @@ namespace Migrations.Migrations.MongoDb
                             var domainType = eventStream.Substring(0, indexOfType);
                             var domainId = eventStream[indexOfId..];
 
-                        if (!eventStream.StartsWith("app-", StringComparison.OrdinalIgnoreCase))
-                        {
                             var newDomainId = DomainId.Combine(DomainId.Create(appId), DomainId.Create(domainId)).ToString();
                             var newStreamName = $"{domainType}-{newDomainId}";