refactor(tests): address PR feedback - rename helper, fix doc, scoped DbConnection

- Rename CreateClientWithoutRedirectFollowing -> CreateClientWithoutAutoRedirect
  (clearer name, avoids double-negative)
- Fix XML doc comment on the helper (was copy-pasted from GetFollowingGetRedirectsAsync)
- Change DbConnection from singleton to scoped with a keep-alive connection,
  preventing SQLite 'database is locked' errors under concurrent requests
- Add Dispose(bool) override to clean up _keepAliveConnection
- Update PR description: correct method name and hosted-service ordering description

Author: BenjaminMichaelis

EssentialCSharp.Web.Tests/ContentRateLimitingTests.cs

@@ -12,7 +12,7 @@ public class ContentRateLimitingTests : IntegrationTestBase
     [Test]
     public async Task ContentEndpoint_ExceedingPerMinuteLimit_Returns429()
     {
-        using HttpClient client = CreateClientWithoutRedirectFollowing();
+        using HttpClient client = CreateClientWithoutAutoRedirect();
 
         // Anonymous limit is 10/min. First 10 requests should not be rate-limited.
         for (int i = 0; i < 10; i++)

EssentialCSharp.Web.Tests/IntegrationTestBase.cs

@@ -8,11 +8,11 @@ namespace EssentialCSharp.Web.Tests;
 public abstract class IntegrationTestBase : WebApplicationTest<WebApplicationFactory, Program>
 {
     /// <summary>
-    /// Executes a GET request and follows redirect responses while preserving
-    /// TUnit trace correlation by using <see cref="TracedWebApplicationFactory{T}.CreateClient()"/>.
-    /// This helper intentionally follows redirects using GET requests only.
+    /// Creates an <see cref="HttpClient"/> with <c>AllowAutoRedirect = false</c> so callers can
+    /// assert exact redirect status codes and <c>Location</c> headers without the client
+    /// silently following them.
     /// </summary>
-    protected HttpClient CreateClientWithoutRedirectFollowing() =>
+    protected HttpClient CreateClientWithoutAutoRedirect() =>
         Factory.Inner.CreateClient(new WebApplicationFactoryClientOptions { AllowAutoRedirect = false });
 
     protected static async Task<HttpResponseMessage> GetFollowingGetRedirectsAsync(

EssentialCSharp.Web.Tests/WebApplicationFactory.cs

@@ -14,7 +14,13 @@ namespace EssentialCSharp.Web.Tests;
 
 public sealed class WebApplicationFactory : TestWebApplicationFactory<Program>
 {
-    private static string SqlConnectionString => $"DataSource=file:{Guid.NewGuid()}?mode=memory&cache=shared";
+    // One GUID per factory instance → each factory gets its own isolated in-memory database.
+    private readonly string _sqlConnectionString =
+        $"DataSource=file:{Guid.NewGuid():N}?mode=memory&cache=shared";
+
+    // Kept open for the factory lifetime so the shared-cache in-memory database is not dropped
+    // when per-scope connections are disposed between requests.
+    private SqliteConnection? _keepAliveConnection;
 
     protected override void ConfigureWebHost(IWebHostBuilder builder)
     {
@@ -48,7 +54,19 @@ protected override void ConfigureWebHost(IWebHostBuilder builder)
                 services.Remove(migrationServiceDescriptor);
             }
 
-            services.AddSingleton<DbConnection>(_ => CreateOpenSqliteConnection());
+            // Open a keep-alive connection to prevent the shared-cache in-memory database from
+            // being dropped when per-scope connections are disposed between requests.
+            _keepAliveConnection = new SqliteConnection(_sqlConnectionString);
+            _keepAliveConnection.Open();
+
+            // Register as scoped so each request scope gets its own SqliteConnection,
+            // preventing "database is locked" errors under concurrent requests.
+            services.AddScoped<DbConnection>(_ =>
+            {
+                SqliteConnection conn = new(_sqlConnectionString);
+                conn.Open();
+                return conn;
+            });
 
             services.AddDbContext<EssentialCSharpWebContext>((serviceProvider, options) =>
             {
@@ -84,11 +102,13 @@ protected override void ConfigureWebHost(IWebHostBuilder builder)
         });
     }
 
-    private static SqliteConnection CreateOpenSqliteConnection()
+    protected override void Dispose(bool disposing)
     {
-        SqliteConnection connection = new(SqlConnectionString);
-        connection.Open();
-        return connection;
+        if (disposing)
+        {
+            _keepAliveConnection?.Dispose();
+        }
+        base.Dispose(disposing);
     }
 
     private sealed class EnsureCreatedHostedService(IServiceProvider serviceProvider) : IHostedService