Разделение

backend/src/Contracts/Messaging/Abstractions/IUserStatsService.cs

@@ -0,0 +1,13 @@
+using System;
+using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace Knot.Contracts.Messaging.Abstractions;
+
+public interface IUserStatsService
+{
+    Task<Dictionary<Guid, UserStats>> GetStatsForUsersAsync(List<Guid> userIds, CancellationToken cancellationToken = default);
+}
+
+public record UserStats(int MessageCount, long StorageSize);