transform operator-prefixed expressions to be parsable on execute

[kevinushey]

Some users might prefer using their binary operators at the start of new lines when building longer expressions; e.g.

foo <- (
  data
  %>% operation1()
  %>% operation2()
  %>% ...
)

While such code is legal as an entire entity, executing subsets of that code is challenging because outside of a parenthetical context:

data
%>% operation1()

is two separate statements, not one (with the second being invalid).

It would be helpful if RStudio transformed such expressions during interactive execution so that they could be executable while maintaining the semantics expected by the user.

[warnes]

Please ensure this can easily be activated/deactivated.

[iago-pssjd]

In line with my comment in issue #8589 and again agree with @warnes I expect to have the chance of configure the suggested behaviour or the current one in RStudio.

Thank you!