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

tests/CBDD.Tests/MetadataPersistenceTests.cs

@@ -14,12 +14,18 @@ public class MetadataPersistenceTests : IDisposable
     private readonly string _dbPath;
     private readonly string _walPath;
 
+    /// <summary>
+    /// Initializes a new instance of the <see cref="MetadataPersistenceTests"/> class.
+    /// </summary>
     public MetadataPersistenceTests()
     {
         _dbPath = Path.Combine(Path.GetTempPath(), $"docdb_meta_{Guid.NewGuid()}.db");
         _walPath = Path.ChangeExtension(_dbPath, ".wal");
     }
 
+    /// <summary>
+    /// Tests index definitions are persisted and reloaded.
+    /// </summary>
     [Fact]
     public void IndexDefinitions_ArePersisted_AndReloaded()
     {
@@ -59,6 +65,9 @@ public class MetadataPersistenceTests : IDisposable
         }
     }
 
+    /// <summary>
+    /// Tests ensure index does not recreate if index exists.
+    /// </summary>
     [Fact]
     public void EnsureIndex_DoesNotRecreate_IfIndexExists()
     {
@@ -91,6 +100,9 @@ public class MetadataPersistenceTests : IDisposable
         }
     }
 
+    /// <summary>
+    /// Disposes the resources used by this instance.
+    /// </summary>
     public void Dispose()
     {
         if (File.Exists(_dbPath)) File.Delete(_dbPath);