feat: AWS Comprehend PII redactor utility

[WeJaWi]

Summary

Implements the AWS Comprehend PII redactor utility requested in #290.

What's included

New package: JS/edgechains/arakoodev/src/pii-redactor/

• AWSComprehendPIIRedactor class with three methods:
  • detectPII(text) — returns detected PII entities with offsets, types, and confidence scores
  • redactPII(text, options) — replaces PII with labeled placeholders [NAME], [EMAIL], etc. or mask characters
  • sanitize(text) — convenience wrapper that returns only the cleaned string, ideal for chaining

Key features:

• Labeled redaction mode (default): "My name is John Doe" → "My name is [NAME]"
• Mask mode: replace with repeated character, e.g. "****"
• Filter by entity type: only redact EMAIL, leave NAME intact
• Configurable language code (en/es/fr/de/it/pt/ar/hi/ja/ko/zh)
• AWS credentials from constructor args or environment variables (AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY, AWS_REGION)
• Entities sorted descending by offset before replacement — prevents offset shifting when multiple PII spans are replaced

Test suite: 9 unit tests using Vitest with fully mocked AWS SDK (no real AWS calls needed to run tests)

Working example: JS/edgechains/examples/pii-redaction-example/

• Hono server with GET /redact?text=... — full chain: Comprehend → sanitize → OpenAI
• GET /redact/detect?text=... — detection only, no LLM call

Usage

import { AWSComprehendPIIRedactor } from "@arakoodev/edgechains.js/pii-redactor";

const redactor = new AWSComprehendPIIRedactor();

// Chain directly with any LLM endpoint
const safePrompt = await redactor.sanitize(userInput);
const response = await openai.chat({ prompt: safePrompt });

Closes #290

[github-actions]

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