Detail should be rendered as shtort one line, just dumping fn header
there is not useful, despite the fact that TS does this.
The fact that this is a function should be indicated by the icon, the
same goes for pub/const/async etc qualitfiers
name is already present in the lable (and arg list should be a part of
that, as in idea)
But the return type is the small genuinerlly useful bit of info we can show here