feat(useTextDirection): new function

[iChengbo]

Description

The dir global attribute is an enumerated attribute that indicates the directionality of the element's text.

Some languages are written from right to left, such as Arabic and Hebrew, So, when using i18n, it needs useDir to get the ref(dir) of the element.

reactive RTL mode. #1168

Additional context

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

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[antfu]

useDir reads a bit too general to me, witch it might be interpreted as Directory or something else. Maybe we could have useRTL or useTextDirection?

[michealroberts]

I would perhaps rename this to useRTLTextDirection() or useTextDirection().

[iChengbo]

@antfu @michealroberts
The useDir is named based on the name of the property,, but it is really a bit confusing. And compared to useRTL and useRTLTextDirection, I think useTextDirection is more appropriate, so I will rename it.