chore: prepare release v0.3.1

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: yepzdk

.claude-plugin/plugin.json

@@ -1,5 +1,5 @@
 {
   "name": "itkdev-tools",
   "description": "ITK Dev tools and MCP servers for Claude Code",
-  "version": "0.3.0"
+  "version": "0.3.1"
 }

CHANGELOG.md

@@ -7,6 +7,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [0.3.1] - 2026-01-27
+
 ### Fixed
 
 - Skills not loading due to incorrect directory structure (#17)
@@ -56,7 +58,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - GitHub guidelines skill for ITK Dev team workflows
 - Plugin marketplace structure
 
-[Unreleased]: https://github.com/itk-dev/itkdev-claude-plugins/compare/v0.3.0...HEAD
+[Unreleased]: https://github.com/itk-dev/itkdev-claude-plugins/compare/v0.3.1...HEAD
+[0.3.1]: https://github.com/itk-dev/itkdev-claude-plugins/compare/v0.3.0...v0.3.1
 [0.3.0]: https://github.com/itk-dev/itkdev-claude-plugins/compare/v0.2.0...v0.3.0
 [0.2.0]: https://github.com/itk-dev/itkdev-claude-plugins/compare/v0.1.0...v0.2.0
 [0.1.0]: https://github.com/itk-dev/itkdev-claude-plugins/releases/tag/v0.1.0