Pinot Data Explorer doesn't support all the Pinot data types

When creating a schema from the Pinot Data Explorer UI, the "datatypes" drop-down only supports primitive data types. It will be nice to add other supported data types like MAP, LIST, STRUCT, and JSON for more accessible exploration.

Start in the Pinot Data Explorer UI flow for creating a schema and inspect how the datatype dropdown is populated. Confirm how existing primitive types are represented, then add support for MAP, LIST, STRUCT, and JSON; done means each type is available when creating a schema.

Written by the indexing model from the issue text.