Bump version to 3.10.3

Author: waylan

docs/changelog.md

@@ -10,11 +10,12 @@ and this project adheres to the
 [Python Version Specification](https://packaging.python.org/en/latest/specifications/version-specifiers/).
 See the [Contributing Guide](contributing.md) for details.
 
-## [Unreleased]
+## [3.10.3] - 2026-07-30
 
 ### Fixed
 
 * Fix `SetextHeaderProcessor` regex to prevent mixed `=` and `-` chars in setext-style headers (#1606).
+* Add AI Policy to Contributing Guide.
 * Officially document all included extensions as being in maintenance mode.
 * Link the Extension API documentation to the API Reference (#1612).
 

markdown/__meta__.py

@@ -28,7 +28,7 @@
 from __future__ import annotations
 
 
-__version_info__ = (3, 10, 2, 'final', 0)
+__version_info__ = (3, 10, 3, 'final', 0)
 
 
 def _get_version(version_info):