NcAppNavigationItem undo has several issues

[HassoSigbjoernson]

When setting undo = true:

the text overflow is broken The overflow of the name isn't hidden anymore, the name can overflow into the content and other elements like the actions are pushed into a second line.

the undo action has no label There doesn't appear to be any way to set a label for the undo action that is created. This is fine if undo is the only action and forceMenu & editable are false but suboptimal if there happens to be a actions menu.

the icon disappears The icon disappears for no apparent reason.