[WIP] Add Chinese version of README file (#14)

* Initial plan

* Add Chinese version of README (README.zh-CN.md)

Co-authored-by: JusterZhu <11714536+JusterZhu@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: JusterZhu <11714536+JusterZhu@users.noreply.github.com>

Author: Copilot

README.md

@@ -10,6 +10,8 @@
 [![.NET](https://img.shields.io/badge/.NET-8.0-purple.svg)](https://dotnet.microsoft.com/download/dotnet/8.0)
 [![Avalonia](https://img.shields.io/badge/Avalonia-11.2-orange.svg)](https://avaloniaui.net/)
 
+English | [简体中文](README.zh-CN.md)
+
 </div>
 
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