Add shared pagination, projections and ownership helpers; simplify query and command handlers

backend/Core/Musify.Application/Users/SyncUser.cs

@@ -3,6 +3,7 @@ using Mediator;
 using Microsoft.EntityFrameworkCore;
 using Microsoft.Extensions.Logging;
 using Musify.Application.Contracts;
+using Musify.Application.Shared;
 using Musify.Domain.Entities;
 
 namespace Musify.Application.Users;
@@ -29,7 +30,7 @@ public class SyncUserCommandHandler(IDatabase database, ILogger<SyncUserCommandH
             {
                 Id = request.Id,
                 Name = request.Name,
-                NormalizedName = request.Name.ToUpperInvariant(),
+                NormalizedName = TextNormalizer.Normalize(request.Name),
                 FirstName = request.FirstName,
                 SecondName = request.SecondName,
                 ProfilePictureUrl = request.ProfilePictureUrl
@@ -38,11 +39,11 @@ public class SyncUserCommandHandler(IDatabase database, ILogger<SyncUserCommandH
             await database.SaveChangesAsync(cancellationToken);
             logger.LogInformation("Provisioned user {UserId}", request.Id);
 
-            return new Success();
+            return Result.Success;
         }
 
         user.Name = request.Name;
-        user.NormalizedName = request.Name.ToUpperInvariant();
+        user.NormalizedName = TextNormalizer.Normalize(request.Name);
         user.FirstName = request.FirstName;
         user.SecondName = request.SecondName;
         user.ProfilePictureUrl = request.ProfilePictureUrl;
@@ -51,6 +52,6 @@ public class SyncUserCommandHandler(IDatabase database, ILogger<SyncUserCommandH
         if (written > 0)
             logger.LogInformation("Synced profile for user {UserId}", request.Id);
 
-        return new Success();
+        return Result.Success;
     }
 }