Merge branch 'rc-v1.5.1'

Author: cpsievert

CHANGELOG.md

@@ -5,7 +5,7 @@ All notable changes to Shiny for Python will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## [UNRELEASED]
+## [1.5.1] - 2025-12-08
 
 ### New features