[ICM CXX] Address Pad kernel shortcomings (#26864)
### Description
Address OOB reads and writes issues.
### Motivation and Context
https://github.com/microsoft/onnxruntime/issues/11828
https://github.com/microsoft/onnxruntime/issues/13332
See also this: https://github.com/onnx/onnx/issues/4294
