[Feature Request]: new transform to obfuscate / mask PII data

### What would you like to happen?

Migration: https://issues.apache.org/jira/browse/HOP-3110

Based on Schrems II, GDPR, and other governing rules for data there is an increased need to make sure PII data is protected when applicable.

Based on a field by field setting, I would like to have an option to modify the contents of a column based on a column matching the criteria. This could be a number of options: obfuscation /masking, null, blank, etc.

Having something like this would allow for metadata driven processing of the data to comply with data processing rules.

### Issue Priority

Priority: 3

### Issue Component

Component: Transforms

Start with the Transforms component and read the linked HOP-3110 migration for the intended scope. Clarify the field-matching rules and supported outcomes—masking, obfuscation, null, or blank—before identifying the relevant transform entry point; done means metadata-driven PII handling is specified and covered by appropriate tests.

Written by the indexing model from the issue text.