Function cublas_bf16_proj_dense 

pub fn cublas_bf16_proj_dense(
    act: DevicePtr,
    weight_bf16: DevicePtr,
    out: DevicePtr,
    m: u32,
    n: u32,
    k: u32,
    stream: u64,
) -> Result<()>

Route a projection out[M,N] = act[M,K] @ weightᵀ through cuBLASLt BF16 for a weight that is already native BF16 [N,K] (no dequant step). Used by models whose attention/shared-expert weights ship unquantized (e.g. Laguna), which can never satisfy the as_fp8() gate of cublas_bf16_proj.