Support Map as a ScalarValue

[Blizzara]

Is your feature request related to a problem or challenge?

ScalarValue does not currently support Maps, see e.g. https://github.com/apache/datafusion/issues/8262#issuecomment-1852700799.

https://github.com/apache/datafusion/issues/6485 is probably related as well, though I'm not 100% sure

I ran into this when looking to implement Substrait -> DF conversion for MapType

Describe the solution you'd like

Implement ScalarValue::Map and all the related functionality

Describe alternatives you've considered

No response

Additional context

No response