KFileWidget: Enable word wrapping for the message widget
The error messages can potentially be long.
Dolphin does some special https://invent.kde.org/system/dolphin/-/blob/master/src/dolphinviewcontainer.cpp#L459 stuff which I don't know if we should replicate here.
It also does some funky bits with the layout at times, so not sure we should merge this right now as-is.