Created by: Xreki

In #9000, the basic Executor.Run was split into two low-level functions, Executor.Prepare and Executor.RunPreparedContext. In Executor.Prepare, operators are created in advance and saved in a ExecutorPrepareContext. We can always call Executor.RunPreparedContext to use the ExecutorPrepareContext instead to avoid frequently creating and destroying of operators if there is no change to the program.

For inference, a high level Executor.Run is defined for direct use in C++ inference codes. We should also provide a corresponding high level Executor.RunPreparedContext if users want to avoid the cost of frequently creating and destroying of operators.