fix(css): use aliased exports for CSS module keys

[wChenonly]

• This PR contains AI-generated code, but I have carefully reviewed it myself. Otherwise, my PR may be closed.

Description

fix the issue where reserved words cannot be exported correctly in CSS modules

add a check for JavaScript reserved words to avoid using reserved words as named exports when exporting CSS modules

reserved words referenced

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Lexical_grammar#reserved_words

Linked Issues

#839

Additional context

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commit: 63e2784

[sxzz]

This is clearly AI vibe-coded. Please be honest and check the checkbox on the PR template accordingly.

[wChenonly]

I am very sure that I did not use it, the only PR I used has been marked

[wChenonly]

I didn't refer to the original CSS for testing. test.ts, I also have tests in my own project, and I've done similar unified test entry points, something like this form, so I just migrated it directly.