onnxruntime

127704c4 - Validate g_idx values in MatMulNBits to prevent OOB read (#27582)

Validate g_idx values in MatMulNBits to prevent OOB read (#27582) ### Description In `Dequantize4BitsKernelReOrder` (CPU and CUDA EP), values from the `g_idx` tensor are used directly as array indices into the `scales` and `zero_points` buffers without bounds checking. This PR adds value-range validation and tests for the `g_idx` input tensor in the `MatMulNBits` operator. ### Motivation and Context <!-- - Why is this change required? What problem does it solve? - If it fixes an open issue, please link to the issue here. --> --------- Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>