Describe the bug

The recent PR #22 added css-modules support, but the code exporting classnames is missing the fact that class names are not a good fit for JS variables:

https://github.com/nicksrandall/unplugin-lightningcss/blob/01f1d485ab119d213b955b69ac3c5065d83875e9/src/core/transform.ts#L49-L54

This causes CSS such like:

.my-class {...}

To fail build due to the error like so:

 2 │ export const my-class = "G6CPCq_my-class";
   │                    │ 
   │                    ╰─ 
   │ 
   │ Help: Try insert a semicolon here

Reproduction

See above

System Info

Any system

Used Package Manager

npm

Validations

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• The provided reproduction is a minimal reproducible of the bug.