Function moe_grouped_down_cutlass 

pub fn moe_grouped_down_cutlass(
    gpu: &dyn GpuBackend,
    eoff_cached: Option<&[i32]>,
    host: &MoeCutlassDownHostTables,
    a: DevicePtr,
    c: DevicePtr,
    expert_offsets: DevicePtr,
    hidden: u32,
    inter: u32,
    stream: u64,
) -> Result<()>

2026-09-25: Single-launch CUTLASS grouped NVFP4 down GEMM through metrale_gpu_runtime::cutlass::nvfp4_grouped_down. a is the expert-sorted post-SiLU intermediate [total_expanded, inter]; expert_offsets is the device prefix sum.