Ignore unexpected properties when deserializing a ContentBlock (#956)

* Ignore unexpected properties when deserializing a ContentBlock

* Fix deserialization of Reference.Title and more bugs for unknown props

* Remove comments about skipping additional properties

src/ModelContextProtocol.Core/Protocol/ResourceContents.cs

@@ -116,6 +116,7 @@ public abstract class ResourceContents
                         break;
 
                     default:
+                        reader.Skip();
                         break;
                 }
             }