Problem: on `CompleteDone` cursor can jump to the end of line instead of
the end of the completed word.
Solution: remove only inserted word for snippet expansion instead of everything
until eol.
Fixes#30656
Co-authored-by: Mathias Fussenegger <f.mathias@zignar.net>
Co-authored-by: Justin M. Keyes <justinkz@gmail.com>