//! FFI API for the Relativity module.
//!
//! This module provides three types of FFI interfaces:
//! - Handle-based API (C-style functions)
//! - JSON-based API (string serialization)
//! - Bincode-based API (binary serialization)
/// bincode-based FFI bindings for Relativity.
/// Handle-based FFI bindings for Relativity using opaque handles.
/// JSON-based FFI bindings for Relativity using serialized data.