//! ARM TrustZone / OP-TEE integration
//!
//! **Status**: Not yet implemented
//!
//! # Planned Features
//!
//! - Secure world key operations via OP-TEE
//! - Trusted Application (TA) for cryptographic operations
//! - Secure storage for keys
//! - Integration with ARM TrustZone hardware
//!
//! # Implementation Plan
//!
//! - [ ] Add OP-TEE client library dependency
//! - [ ] Develop Trusted Application (TA) for key operations
//! - [ ] Implement `TrustZoneProvider` struct
//! - [ ] Implement `SecureKeyProvider` trait for TrustZone
//! - [ ] Add TA deployment and provisioning
//! - [ ] Add tests with QEMU TrustZone emulation
// TODO: Implementation requires OP-TEE development environment
// Need to create TA (Trusted Application) in addition to normal world client