Task Description

What needs to be done:
Introduce the new Variant schema type. This will look similar to a record/struct with a logical type associated with it, see the parquet spec for reference.

Validation should be done to ensure that this context can be persisted as part of the schema string and then read back. For older Hudi versions, they should be able to read back this type but lose the context. This will ensure backwards compatibility.

Why this task is needed:
This is the first step towards adding support for the Variant type throughout Hudi.

Task Type

Code improvement/refactoring

Related Issues

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