refactor(css): use preliminaryFileName to detect pure CSS chunks

[sapphi-red]

Description

A better way to handle the non finalized filenames (!~{001}~).
I came up with this while thinking about #11671 (comment)

related: rollup/rollup#5080

Additional context

---

What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

Before submitting the PR, please make sure you do the following

• Read the Contributing Guidelines.
• Read the Pull Request Guidelines and follow the PR Title Convention.
• Check that there isn't already a PR that solves the problem the same way to avoid creating a duplicate.
• Provide a description in this PR that addresses what the PR is solving, or reference the issue that it solves (e.g. fixes #123).
• Ideally, include relevant tests that fail without this PR but pass with it.

[stackblitz]

Run & review this pull request in StackBlitz Codeflow.

[bluwy]

Looks great! I think I initially didn't went with it because I wasn't sure if RenderedChunk and bundled chunk are sharing the same instance, but it looks like it does so great to use that instead until Rollup also supports the new prop.

[sapphi-red]

Changed to use preliminaryFileName instead of viteNonFinalizedFilename.