Statement range executions currently aren't considered as `input_reply`s, is that right?

Check out this RStudio behavior where if we send input to the console from an editor with Cmd + Enter, then that input is used when we are in a readline() prompt:

https://github.com/user-attachments/assets/60578f31-c180-4c0f-95d4-0e538a953cab

Compare that with Positron, where instead the input is sent into a queue that only runs after the user manually types something into the Console

https://github.com/user-attachments/assets/f3f1c897-9e8a-43c7-9084-01381fbd6ff3

This briefly surprised me when creating this reprex. I had all the aaaaas in the editor and sent them to the console with cmd+enter.
https://github.com/posit-dev/ark/pull/536#discussion_r1773822974

Admittedly I never do this in practice, and could see an argument for requiring an "input reply" to be actual user input physically typed into the console (meaning there would not be a bug here). If that's the case, I think we should add a test for this case to prove to our future selves that we have thought about this behavior.

Start by tracing how console input reaches a readline() prompt, using the behavior comparison and the discussion on ark#536 as context. Determine whether statement-range executions should count as input replies; completion means either matching RStudio's behavior with a regression test or documenting and testing the intentional queueing behavior.