refactor: rename handle_patronymic_name_order to handle_east_slavic_patronymic_name_order

Consistency fix: this handler only ever implemented East-Slavic
rotation logic (sibling to handle_turkic_patronymic_name_order()), so
the generic name was misleading now that a family-specific sibling
exists — the same asymmetry that is_patronymic -> is_east_slavic_patronymic
already fixed for the helper method. The patronymic_name_order flag
itself stays generic, since it's the public umbrella opt-in switch
covering both families by design.

Pure rename, zero behavior change — single call site, not referenced
by name in shipped docs.

Author: derek73

nameparser/parser.py

@@ -757,7 +757,7 @@ def pre_process(self) -> None:
         self.parse_nicknames()
         self.squash_emoji()
 
-    def handle_patronymic_name_order(self) -> None:
+    def handle_east_slavic_patronymic_name_order(self) -> None:
         """
         When patronymic_name_order is enabled, detect Russian formal order
         (Surname GivenName Patronymic) and rotate to Western order.
@@ -818,7 +818,7 @@ def post_process(self) -> None:
         """
         self.handle_firstnames()
         if self.C.patronymic_name_order:
-            self.handle_patronymic_name_order()
+            self.handle_east_slavic_patronymic_name_order()
             self.handle_turkic_patronymic_name_order()
         if self.C.middle_name_as_last:
             self.handle_middle_name_as_last()