This adds nimsuggest support for displaying inlay hints for exceptions.
An inlay hint is displayed around function calls, that can raise an
exception, which isn't handled in the current subroutine (in other
words, exceptions that can propagate back to the caller). On mouse hover
on top of the hint, a list of exceptions that could propagate is shown.

The changes, required to support this are already commited to
nimlangserver and the VS code extension. The extension and the server
allow configuration for whether these new exception hints are enabled
(they can be enabled or disabled independently from the type hints), as
well as the inlay strings that are inserted before and after the name of
the function, around the function call. Potentially, one of these
strings can be empty, for example, the user can choose to add an inlay
hint only before the name of the function, or only after the name of the
function.

(cherry picked from commit 899ba01)