How do you center an iconbutton inside the persistentFooterButtons?

I've tried different things like wrapping my icon button inside a row, iand using cross alignment. I've tried using `center` which would make the section full page and centered vertically rather than horizontally.


I want the + icon in the center and I'm a little lost at how to make that happen.

The issue names no repository file, test, or example to inspect, and provides no code beyond the Flutter API names. Start by reproducing the layout with persistentFooterButtons and IconButton in a minimal Flutter example; done would require a confirmed implementation path or a documented example showing the icon centered horizontally.

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