feat: добавил личные уведомления для пользователей

Реализовал хранение, получение и отметку прочитанными пользовательских уведомлений. Обновил фронтенд для отображения и управления уведомлениями в профиле студента.

backend/UniVerse.Api.Tests/Gamification/GamificationServiceTests.cs

@@ -1,6 +1,9 @@
 using Microsoft.EntityFrameworkCore;
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.Logging.Abstractions;
+using NSubstitute;
+using UniVerse.Application.DTOs.Notifications;
+using UniVerse.Application.Interfaces;
 using UniVerse.Domain.Entities;
 using UniVerse.Domain.Enums;
 using UniVerse.Infrastructure.Data;
@@ -105,6 +108,17 @@ public class GamificationServiceTests
 
     private static GamificationService CreateService(AppDbContext db)
     {
+        var notifications = Substitute.For<INotificationService>();
+        notifications.CreateUserNotificationAsync(
+                Arg.Any<int>(),
+                Arg.Any<string>(),
+                Arg.Any<string>(),
+                Arg.Any<string>(),
+                Arg.Any<CancellationToken>())
+            .Returns(callInfo => new UserNotificationDto(1, callInfo.ArgAt<string>(1), callInfo.ArgAt<string>(2), callInfo.ArgAt<string>(3), false, DateTime.UtcNow));
+        notifications.SendAsync(Arg.Any<NotificationMessage>(), Arg.Any<CancellationToken>())
+            .Returns(Task.CompletedTask);
+
         var configuration = new ConfigurationBuilder()
             .AddInMemoryCollection(new Dictionary<string, string?>
             {
@@ -114,7 +128,7 @@ public class GamificationServiceTests
             })
             .Build();
 
-        return new GamificationService(db, configuration, NullLogger<GamificationService>.Instance);
+        return new GamificationService(db, configuration, notifications, NullLogger<GamificationService>.Instance);
     }
 
     private static Achievement Achievement(int id, string name, string condition, int coinReward) => new()