dataTable : <th> is hidden by <td> with frozenColumn

[quentin-ineat-ca]

Describe the bug

Like the title says, inside dataTable component, the header is hidden by cell from body when you start to scroll.
Header goes behind the content when you scroll as the same z-index is shared.

You can see it in the doc too : https://primeng.org/table#frozen-columns

Maybe also introduced with the new "@ layer" from 16.4.0 (introducing breaking changes for a minor version in my opinion by changing CSS order).

Working again if you remove the z-index introduced in PR #13590.

Inside inspect :

Exemple when start to scroll :

Environment

Company app using datatable with lazyload and selection.

Reproducer

https://primeng.org/table#frozen-columns

Angular version

16.2.7

PrimeNG version

16.4.1

Build / Runtime

Angular CLI App

Language

TypeScript

Node version (for AoT issues node --version)

18.17.1

Browser(s)

Chrome 117

Steps to reproduce the behavior

No response

Expected behavior

Header inside table should stay visible when you scroll.