[Feature Request][Kernel] Consolidate recursive code to SchemaIterable where appropriate.

[emkornfield]

Feature request

Which Delta project/connector is this regarding?

• Spark
• Standalone
• Flink
• Kernel
• Other (fill in here)

Overview

SchemaIterable has been introduced as a general way to iterate/update schemas. Refactor code as appropriate to consolidate on this abstraction.

Motivation

There are multiple customer recursion paths in the code base, using SchemaIterable as a common abstraction leads to more idiomatic and small code.

Further details

N/A

Willingness to contribute

The Delta Lake Community encourages new feature contributions. Would you or another member of your organization be willing to contribute an implementation of this feature?

• Yes. I can contribute this feature independently.
• Yes. I would be willing to contribute this feature with guidance from the Delta Lake community.
• No. I cannot contribute this feature at this time.