Fix audit findings for coverage, architecture checks, and XML docs

tests/CBDD.Tests/CdcScalabilityTests.cs

@@ -13,12 +13,18 @@ public class CdcScalabilityTests : IDisposable
     private readonly Shared.TestDbContext _db;
     private readonly string _dbPath;
 
+    /// <summary>
+    /// Initializes a new instance of the <see cref="CdcScalabilityTests"/> class.
+    /// </summary>
     public CdcScalabilityTests()
     {
         _dbPath = Path.Combine(Path.GetTempPath(), $"cdc_scaling_{Guid.NewGuid()}.db");
         _db = new Shared.TestDbContext(_dbPath);
     }
 
+    /// <summary>
+    /// Verifies CDC dispatch reaches all registered subscribers.
+    /// </summary>
     [Fact]
     public async Task Test_Cdc_1000_Subscribers_Receive_Events()
     {
@@ -55,6 +61,9 @@ public class CdcScalabilityTests : IDisposable
         foreach (var sub in subscriptions) sub.Dispose();
     }
 
+    /// <summary>
+    /// Verifies a slow subscriber does not block other subscribers.
+    /// </summary>
     [Fact(Skip = "Performance test - run manually when needed")]
     public async Task Test_Cdc_Slow_Subscriber_Does_Not_Block_Others()
     {
@@ -99,6 +108,9 @@ public class CdcScalabilityTests : IDisposable
         slowEventCount.ShouldBe(2);
     }
 
+    /// <summary>
+    /// Disposes test resources and removes temporary files.
+    /// </summary>
     public void Dispose()
     {
         _db.Dispose();