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

tests/CBDD.Tests/DocumentCollectionDeleteTests.cs

@@ -14,6 +14,9 @@ public class DocumentCollectionDeleteTests : IDisposable
     private readonly string _walPath;
     private readonly Shared.TestDbContext _dbContext;
 
+    /// <summary>
+    /// Initializes a new instance of the <see cref="DocumentCollectionDeleteTests"/> class.
+    /// </summary>
     public DocumentCollectionDeleteTests()
     {
         _dbPath = Path.Combine(Path.GetTempPath(), $"test_delete_{Guid.NewGuid()}.db");
@@ -22,11 +25,17 @@ public class DocumentCollectionDeleteTests : IDisposable
         _dbContext = new Shared.TestDbContext(_dbPath);
     }
 
+    /// <summary>
+    /// Releases test resources.
+    /// </summary>
     public void Dispose()
     {
         _dbContext.Dispose();
     }
 
+    /// <summary>
+    /// Verifies delete removes both the document and its index entry.
+    /// </summary>
     [Fact]
     public void Delete_RemovesDocumentAndIndexEntry()
     {
@@ -52,6 +61,9 @@ public class DocumentCollectionDeleteTests : IDisposable
         all.ShouldBeEmpty();
     }
 
+    /// <summary>
+    /// Verifies delete returns false for a non-existent document.
+    /// </summary>
     [Fact]
     public void Delete_NonExistent_ReturnsFalse()
     {
@@ -61,6 +73,9 @@ public class DocumentCollectionDeleteTests : IDisposable
         deleted.ShouldBeFalse();
     }
 
+    /// <summary>
+    /// Verifies deletes inside a transaction commit successfully.
+    /// </summary>
     [Fact]
     public void Delete_WithTransaction_CommitsSuccessfully()
     {