Refactor: factorize IgnoredProperties extension in Document class

Move `extend IgnoredProperties` from NestedDocument and Base classes to their parent Document class to eliminate code duplication. Since both NestedDocument and Base inherit from Document, they automatically gain access to the ignored_properties functionality without redundant extend statements.

This refactoring improves code maintainability and ensures any future Document subclasses will also have access to ignored_properties.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: pimpin

lib/couchbase-orm/base.rb

@@ -46,6 +46,7 @@ class Document
         include Encrypt
 
         extend Enum
+        extend IgnoredProperties
 
         define_model_callbacks :initialize, :only => :after
 
@@ -110,8 +111,6 @@ def serialized_attributes
     end
 
     class NestedDocument < Document
-        extend IgnoredProperties
-
         def initialize(*args, **kwargs)
             super
             if respond_to?(:id) && id.nil?
@@ -136,7 +135,6 @@ class Base < Document
         extend EnsureUnique
         extend HasMany
         extend Index
-        extend IgnoredProperties
         extend JsonSchema::Validation
         extend PropertiesAlwaysExistsInDocument