HIPAA-Compliant Patient Data Anonymization Pipeline

Create a Node.js data processing script that automatically sanitizes patient records by removing personally identifiable information (PII) using advanced regex and encryption techniques. The script must handle HL7 FHIR standard JSON files, replace sensitive fields with hashed identifiers, and generate comprehensive anonymization logs with timestamp and transformation details. Implement robust error handling and ensure HIPAA compliance with AES-256 encryption for any remaining sensitive metadata.