Implement a transformation dataflow using XSLT and validate transformed data using Schematron.

Implement a transformation dataflow using XSLT and validate transformed data using Schematron.

This is a larger undertaking and need to be designed and broken down into smaller issues. The focus of this issue is to generate design documentation for this feature.

No files or tests are named. Start by defining the design for an XSLT transformation dataflow and Schematron validation, then break the larger feature into smaller issues. Done means the design documentation captures the proposed approach and actionable follow-up work.

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