Support DuckDB style stuct syntax

[alamb]

Is your feature request related to a problem or challenge?

To make it easier to use structs with DataFusion, having a nicer literal syntax is useful

Describe the solution you'd like

It would be nice to support duckdb style struct syntax:

https://duckdb.org/docs/sql/data_types/struct

SELECT {'yes': 'duck', 'maybe': 'goose', 'huh': NULL, 'no': 'heron'};

Describe alternatives you've considered

One way to support this feature would be to implement some Expr variant for the struct literal,

Additional context

@gstein is adding named_struct in this function #9743

@jayzhan211 filed sqlparser-rs/sqlparser-rs#1194 for the upstream sqlparser support