HIPAA-Compliant Patient Data Encryption Middleware

Design a Laravel middleware that automatically encrypts and decrypts sensitive patient health information (PHI) at rest and in transit, using AES-256 encryption. Implement robust key management that integrates with AWS Key Management Service, ensures zero storage of plain-text credentials, and provides comprehensive audit logging for each encryption/decryption event. The middleware must be compatible with Laravel Eloquent models and support transparent encryption for database fields like medical history, contact information, and diagnostic notes.