Apply suggestions from code review

Author: BenjaminMichaelis

EssentialCSharp.Web/Middleware/ReferralTrackingMiddleware.cs

@@ -1,13 +1,13 @@
 using System.Security.Claims;
 using System.Web;
 using EssentialCSharp.Web.Areas.Identity.Data;
-using EssentialCSharp.Web.Services;
+using EssentialCSharp.Web.Services.Referrals;
 using Microsoft.AspNetCore.Http.Extensions;
 using Microsoft.AspNetCore.Identity;
 
 namespace EssentialCSharp.Web.Middleware;
 
-public class ReferralMiddleware
+public sealed class ReferralMiddleware
 {
     private readonly RequestDelegate _Next;
 
@@ -23,7 +23,7 @@ public async Task InvokeAsync(HttpContext context, IReferralService referralServ
         string? referralId = query["rid"];
         string? userReferralId;
 
-        if (context.User is { } claimsUser && claimsUser.Identity is not null && claimsUser.Identity.IsAuthenticated)
+        if (context.User is { Identity.IsAuthenticated: true } claimsUser)
         {
             if (!string.IsNullOrWhiteSpace(referralId))
             {

EssentialCSharp.Web/Program.cs

@@ -4,6 +4,7 @@
 using EssentialCSharp.Web.Extensions;
 using EssentialCSharp.Web.Middleware;
 using EssentialCSharp.Web.Services;
+using EssentialCSharp.Web.Services.Referrals;
 using Mailjet.Client;
 using Microsoft.AspNetCore.HttpOverrides;
 using Microsoft.AspNetCore.Identity;

EssentialCSharp.Web/Services/IReferralService.cs renamed to EssentialCSharp.Web/Services/Referrals/IReferralService.cs

@@ -1,9 +1,9 @@
 using System.Security.Claims;
 
-namespace EssentialCSharp.Web.Services;
+namespace EssentialCSharp.Web.Services.Referrals;
 
 public interface IReferralService
 {
-    Task<bool> TrackReferralAsync(string referralId, ClaimsPrincipal? user);
+    Task TrackReferralAsync(string referralId, ClaimsPrincipal? user);
     Task<string?> GetReferralIdAsync(string userId);
 }

EssentialCSharp.Web/Services/ReferralService.cs renamed to EssentialCSharp.Web/Services/Referrals/ReferralService.cs

@@ -5,7 +5,7 @@
 using Microsoft.EntityFrameworkCore;
 using Sqids;
 
-namespace EssentialCSharp.Web.Services;
+namespace EssentialCSharp.Web.Services.Referrals;
 
 public class ReferralService(EssentialCSharpWebContext dbContext, SqidsEncoder<int> sqids, UserManager<EssentialCSharpWebUser> userManager) : IReferralService
 {
@@ -25,7 +25,7 @@ public class ReferralService(EssentialCSharpWebContext dbContext, SqidsEncoder<i
             }
             else
             {
-                Random random = new();
+                Random random = Random.Shared;
                 string referrerId = sqids.Encode(random.Next());
                 user.ReferrerId = referrerId;
 
@@ -41,7 +41,7 @@ public class ReferralService(EssentialCSharpWebContext dbContext, SqidsEncoder<i
     /// </summary>
     /// <param name="referralId">The referrer ID to track.</param>
     /// <returns>True if the referral was successfully tracked, otherwise false.</returns>
-    public async Task<bool> TrackReferralAsync(string referralId, ClaimsPrincipal? user)
+    public async Task TrackReferralAsync(string referralId, ClaimsPrincipal? user)
     {
         EssentialCSharpWebUser? claimsUser = user is null ? null : await userManager.GetUserAsync(user);
         if (claimsUser is null)