Module backend 

Multi-Backend Abstraction

Provides a unified interface for different GPU backends:

• CUDA (NVIDIA) - Primary, uses PTX
• WGPU (WebGPU) - Cross-platform, uses WGSL (Vulkan/Metal/DX12/WebGPU)
• Metal (Apple) - Native Apple GPU compute via manzana crate
• Vulkan (cross-platform, future)

Structs

CudaBackend

CUDA backend (NVIDIA GPUs)

MetalBackend

Metal backend (Apple GPUs)

VulkanBackend

Vulkan backend (cross-platform) - placeholder

WgpuBackend

WGPU backend (WebGPU - cross-platform via wgpu crate)

Traits

Backend

Backend trait for GPU operations

Functions

detect_backend

Detect best available backend