Problem
The quick-access description text in the header ("Ajouter un tableau à vos favoris pour créer un raccourci dans cette barre.") is truncated and clipped on smaller viewports or when using longer localized strings.
This causes the instructional message to be cut off mid-sentence, making it unreadable for users.

What this change does
This PR modifies the CSS for the header quick-access bar to allow text wrapping and removes the horizontal scrollbar:

Changes white-space from nowrap to normal to allow text wrapping
Changes overflow from hidden/auto to visible to prevent clipping
Adds flex-wrap: wrap to allow content to flow naturally
Adds responsive handling for tablet viewports with max-width: 300px
This improves readability for all localized strings, especially longer translations like French.

Related issue
closes #6107