fix(runtime): nextjs localstorage is not defined

[sukbearai]

add utils/isSSR

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[sukbearai]

[sukbearai]

https://github.com/cyberbear181/sunmao-arco-next.git 添加 sunmao-ui 到 next 项目,ssr渲染模式下会报错

[tanbowensg]

挺好的，不过isSSR在runtime和editor里面都写一遍就重复了。应该把他放到 shared 目录中。然后runtime和editor各自从@sunmao/shared 中去 import 进来。

[tanbowensg]

另外不要使用绝对路径，使用相对路径，否则 CI 会挂。不过改成@sunmao/shared应该就不会有引用路径问题了。