Update to support structured metadata

[jordanpadams]

Are you sure this is not a new requirement or bug?

Yes

Task Type

Sub-task

💡 Description

Update peppi to support the new structured metadata format in the PDS Registry. This includes updating any queries, field mappings, or data processing logic that relies on the legacy flat metadata format.

Related:

• Complete Transition to Full Structured XML Metadata in Registry registry-api#768 (B18 structured XML theme)