Contrib-Op Shape-Inference Output-Index Safety

Reusable method for finding and fixing the bug class where an operator's TypeAndShapeInference function guards an output write with getNumOutputs() > N but then writes an output index greater than N. For a node that declares fewer outputs, the written index is past the end of the inference context's output vector.

Scope: schema-level shape inference in onnxruntime/core/graph/contrib_ops/*.cc and shape_inference_functions.cc. This runs once during Graph::Resolve (model-load time), EP-agnostic - there is no per-EP (CPU/CUDA/ROCm) kernel duplicate of this code to chase. Op kernels allocate outputs via the bounds-safe OpKernelContext::Output(index) and are a separate concern.

1. The pattern