Function w8a16_gemv_silu_input 

pub fn w8a16_gemv_silu_input(
    gpu: &dyn GpuBackend,
    kernel: KernelHandle,
    gate_out: DevicePtr,
    up_out: DevicePtr,
    weight: DevicePtr,
    block_scale: DevicePtr,
    output: DevicePtr,
    n: u32,
    k: u32,
    stream: u64,
) -> Result<()>

2026-09-25: FP8 E4M3 GEMV whose activation is silu(gate_out) * up_out, computed per element from the two [k] BF16 vectors inside the kernel. block_scale is FP32 [n/128, k/128].