Refactor IPAM model classes to use records for Address, Subnetwork, Vlan, Vrf, Section, Tag, Domain, Nameserver, and Session; enhance documentation and implement value equality for records.

classlib.tests/Models/NameserverTests.cs

@@ -57,7 +57,7 @@ public class NameserverTests
     }
 
     [Fact]
-    public void Constructor_WithEmptyNameservers_ReturnsArrayWithEmptyString()
+    public void Constructor_WithEmptyNameservers_ReturnsEmptyArray()
     {
         // Arrange
         var nameServersString = "";
@@ -65,9 +65,8 @@ public class NameserverTests
         // Act
         var nameserver = new Nameserver(1, "Test", nameServersString, "", "", null);
 
-        // Assert
-        nameserver.NameServers.Should().HaveCount(1);
-        nameserver.NameServers[0].Should().BeEmpty();
+        // Assert - Empty entries are excluded
+        nameserver.NameServers.Should().BeEmpty();
     }
 
     [Fact]
@@ -79,4 +78,27 @@ public class NameserverTests
         // Assert
         nameserver.EditDate.Should().BeNull();
     }
+
+    [Fact]
+    public void Constructor_WithSemicolonOnlyString_ReturnsEmptyArray()
+    {
+        // Arrange - edge case with just semicolons
+        var nameServersString = ";;;";
+
+        // Act
+        var nameserver = new Nameserver(1, "Test", nameServersString, "", "", null);
+
+        // Assert
+        nameserver.NameServers.Should().BeEmpty();
+    }
+
+    [Fact]
+    public void ToString_ReturnsName()
+    {
+        // Arrange
+        var nameserver = new Nameserver(1, "Google DNS", "8.8.8.8", "", "", null);
+
+        // Act & Assert
+        nameserver.ToString().Should().Be("Google DNS");
+    }
 }