.Net: Improve mapper effeciency for pinecone and redis hashsets.

[westey-m]

Motivation and Context

Originally we optimized for flexibility when mapping from storage to data models, but this comes at a cost of efficiency.

#9025

Description

• Updating Redis HashSets and Pinecone mappers to not use Json as an intermediary
• Adding restrictions around the types of enumerables supported and that the data model needs a public parameterless constructor.

Contribution Checklist

• The code builds clean without any errors or warnings
• The PR follows the SK Contribution Guidelines and the pre-submission formatting script raises no violations
• All unit tests pass, and I have added new tests where possible
• I didn't break anyone 😄