Clear and concise description of the problem

I enabled preserveModules and cssCodeSplit in library mode.
But css files don't follow the preserveModules rule, use the original module name as the file name.

related code:

Suggested solution

I want to use the original module name as the file name as required by preserveModules when cssCodeSplit is enabled.

Alternative

No response

Additional context

No response

Validations

• Follow our Code of Conduct
• Read the Contributing Guidelines.
• Read the docs.
• Check that there isn't already an issue that request the same feature to avoid creating a duplicate.