Function fp8_gemm_n128_row_scaled_m16 

pub fn fp8_gemm_n128_row_scaled_m16(
    gpu: &dyn GpuBackend,
    kernel: KernelHandle,
    input: DevicePtr,
    weight: &Fp8DenseWeight,
    output: DevicePtr,
    m: u32,
    n: u32,
    k: u32,
    stream: u64,
) -> Result<()>

2026-09-25: fp8_gemm_n128_row_scaled through the single-warp kernel fp8_gemm_t_row_scaled_m16, whose M tile is 16 rows. The grid has no M dimension, so m must be at most 16: rows past the tile are not computed.