docs: Add CI build status badge to README

- Add Build Status badge showing GitHub Actions CI workflow status
- Badge shows green/red status and links to Actions page
- Helps users quickly see if the latest version is working
- Positioned prominently with other project status badges

Author: Alex J Lennon

README.md

@@ -1,6 +1,7 @@
 # WIC Editor
 
 [![License: GPL v3](https://img.shields.io/badge/License-GPLv3-blue.svg)](https://www.gnu.org/licenses/gpl-3.0)
+[![Build Status](https://github.com/DynamicDevices/wic-editor/workflows/CI/badge.svg)](https://github.com/DynamicDevices/wic-editor/actions)
 [![GitHub release](https://img.shields.io/github/release/DynamicDevices/wic-editor.svg)](https://github.com/DynamicDevices/wic-editor/releases)
 [![GitHub issues](https://img.shields.io/github/issues/DynamicDevices/wic-editor.svg)](https://github.com/DynamicDevices/wic-editor/issues)
 [![GitHub stars](https://img.shields.io/github/stars/DynamicDevices/wic-editor.svg)](https://github.com/DynamicDevices/wic-editor/stargazers)