/claim #290

Summary:

• Add AwsComprehendRedactor to the JS AI package using AWS Comprehend DetectPiiEntities.
• Redact plain text, prompt inputs, and chat message arrays before passing them to existing endpoint classes.
• Export the utility from @arakoodev/edgechains.js/ai, add a usage example, and cover masking/filtering behavior with tests.

Verification:

• npx vitest run src/ai/src/tests/awsComprehendRedactor.test.ts
• npx tsc -b