Support dictionary array in C data interface

[sunchao]

Is your feature request related to a problem or challenge? Please describe what you are trying to do.

Currently it seems the Arrow FFI interface doesn't support dictionary yet. Even though the field exists in FFI_ArrowArray, it is never assigned or used.

Unlike the C++ implementation, ArrayData doesn't have a dictionary field either.

Describe the solution you'd like

I haven't looked closely, but I think roughly we should have dictionary in ArrayData first? after that exporting it via the FFI will be straightforward.

Describe alternatives you've considered
N/A

Additional context
N/A

[sunchao]

DictionaryArray also needs change as it is currently not C data interface compatible - when exporting to ArrayData it needs to populate the dictionary field in the output.