onnxruntime

Fail model loading if node input is a missing value (#7459)

* Add check for a node with an invalid input so we fail during model load. Without this we get a more cryptic failure in the allocation planner.

* Add handling for manually created subgraph where outer scope node arg names are in a different place.

* Update onnxruntime/core/graph/graph.cc

Co-authored-by: Pranav Sharma <prs@microsoft.com>

* Ignore Fused nodes when checking inputs are valid. DML EP will remove initializers it has moved across, so they're available when the node runs but are no longer part of the ORT Graph instance.

We have to fully resolve the graph before any node fusion happens, so the model was valid in the beginning (which is the main thing we are trying to validate).

* Skip check in training build. Rules for allowing an 'invalid' input are unknown for those scenarios.

* Only check the initial load for a training build.

Co-authored-by: Pranav Sharma <prs@microsoft.com>