docs: 在 README 顶部添加 Star 引导语（中英双语）

将高克隆量转化为 Star：在标题/徽章下方加一行 'Star if useful' 引导语

Author: truman-t3

README.md

@@ -10,6 +10,9 @@
 
 English | [中文](#chinese)
 
+> ⭐ **If this project helped you, a star is the easiest way to say thanks — and helps others find it.**
+> 若这个项目对你有用，点个 Star 就是最简单的鼓励，也能帮更多人发现它。
+
 > **▶ Live examples:** https://truman-t3.github.io/tinted-ui-tokens-skills/examples/ — four brand colors (blue / green / warm / violet), light + dark, WCAG AA guaranteed. Source in [`examples/`](examples/).
 
 A **cross-agent** skill that turns one brand color into a complete,