Function dense_gemv_batchm 

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

2026-09-25: Dense BF16 GEMV for M rows, C[t] = A[t] @ B^T for t in [0, M), reading the weight once for all rows. Each row follows dense_gemv_bf16’s K order and reduction (gb10 kernels).

input: [M, K] BF16, contiguous; output: M rows at output + t * out_stride (BF16 elements). Refuses m outside 1..=DENSE_GEMV_BATCHM_MAX_M.

Kernel: dense_gemv_bf16_batchm(A, B, C, M, N, K, out_stride)