update AI initializing

rework AIAvailabilityStatus events to mediatr

Azaion.Common/Services/AnnotationService.cs

@@ -21,6 +21,7 @@ using RabbitMQ.Stream.Client.Reliable;
 namespace Azaion.Common.Services;
 
 // SHOULD BE ONLY ONE INSTANCE OF AnnotationService. Do not add ANY NotificationHandler to it!
+// Queue consumer should be created only once.
 public class AnnotationService : IAnnotationService
 {
     private readonly IDbFactory _dbFactory;