chore: replace flag emojis with text labels in README language switcher (#11863)

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

README.md

@@ -11,7 +11,7 @@ An out-of-box UI solution for enterprise applications as a React boilerplate.
 [![Checked with Biome](https://img.shields.io/badge/Checked_with-Biome-60a5fa?style=flat&logo=biome)](https://biomejs.dev)
 [![Ant Design](https://badgen.net/badge/icon/Ant%20Design?icon=https://gw.alipayobjects.com/zos/antfincdn/Pp4WPgVDB3/KDpgvguMpGfqaHPjicRK.svg&label)](https://ant.design/)
 
-Language: 🇺🇸 | [🇨🇳](./README.zh-CN.md)
+Language: English | [简体中文](./README.zh-CN.md)
 
 <img width="1718" height="1191" alt="light theme preview" src="https://github.com/user-attachments/assets/74ad0b4a-e086-4955-8edd-9f2cff31aee8" />
 <img width="1718" height="1191" alt="dark theme preview" src="https://github.com/user-attachments/assets/d4bcb7c1-42c7-4c0f-b130-1193a931f9f7" />

README.zh-CN.md

@@ -1,4 +1,4 @@
-Language : [🇺🇸](./README.md) | 🇨🇳
+Language : [English](./README.md) | 简体中文
 
 <h1 align="center">Ant Design Pro</h1>