Create workspace setting for REPL Smart Send

[anthonykim1]

Resolves: #22318
Create user settings for REPL Smart Send that user can toggle on and off. Will be useful if they have old Python code and want to go back to old "always run line by line when shift entering", regardless of explicit selection or highlight.

[karrtikr]

I think this should be a workspace setting instead, as Python 2 code may reside just in one folder, and other folders might be fine. The notification that we display to the user should offer turn off smart send for either the current workspace folder or all repositories (in which case we modify the user setting).