Function dequant_nvfp4_e8m0_to_bf16 

pub fn dequant_nvfp4_e8m0_to_bf16(
    packed: &[u8],
    scales: &[u8],
    n: usize,
    k: usize,
) -> Result<Vec<u16>>

2026-09-25: Same unpack, then numeric::f32_to_bf16 per element.