Function dequantize_row_into 

pub fn dequantize_row_into(
    raw: &[u8],
    ggml_type: u32,
    n_elems: usize,
    out: &mut [f32],
) -> Result<usize, GgmlDequantError>

Dequantize one embedding row from raw mmap bytes into out. Returns the number of f32 elements written (≤ out.len()).