update changelog

Author: Phil Varner

stapi-fastapi/CHANGELOG.md

@@ -4,6 +4,16 @@ All notable changes to this project will be documented in this file.
 
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/) and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
+## Unreleased
+
+### Changed
+
+- The GetOrder, GetOrders, and GetOrderStatuses Callable aliases are refactored into two classes (GetOrders and GetOrderStatus) that
+  must be implemented instead.  These are genericized to allow appropriate type annotations such that FastAPI will correctly serialize
+  subclasses of OrderStatus.
+- The use of the RootRouter class in ProductRouter are refactored to use two Protocols (ConformancesSupport and RootProvider), so as
+  to decouple the actual (generified) RootRouter from the uses in that class.
+
 ## [0.8.0] - 2025-12-18
 
 ### Added