onnxruntime

Throw if unique_ptr or array allocation fails due to SafeInt overflow (#18941)

### Description
<!-- Describe your changes. -->
If we fail to calculate the buffer size (due to overflow) we currently
return a nullptr. This is inconsistent as an actual memory allocation
failure throws. An overflow would typically be due to bad input so an
exception makes more sense given that.

Change to throw so code using MakeUniquePtr* and AllocArray* doesn't
need to check for nullptr.

Add some extra info to the log message to help debugging.

### 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. -->
Should help with #18905 by avoiding the invalid attempted usage of a
nullptr from the allocation. Extra info _might_ help with figuring out
where the overflow is coming from which is the real issue.