Cua Driver native ABI

cua_driver_abi.h is the stable native interoperability boundary below the public Cua Driver SDK. Release archives place it beside the platform shared library.

The ABI uses versioned symbols, opaque handles, explicit buffer ownership, and callbacks for asynchronous work. Call cua_driver_abi_version_v1 and cua_driver_abi_is_compatible_v1 before creating a driver. Every returned CuaDriverBuffer must be released with cua_driver_buffer_free_v1; driver and operation release functions accept pointer-to-pointer values and are idempotent after clearing them.

Applications should normally use the safe Rust, Python, or TypeScript SDK. The C ABI exists for native embedding and to keep those SDKs independent of the private language used to implement the core.