Scripting: fix CLI REPL error reporting behavior

discrepancy after switching to the new REPL internals was
discovered also on IJ plugin tests, so added a test emulating it.
also some test infra refactoring

compiler/testData/repl/syntaxErrors.repl

@@ -2,6 +2,9 @@
 error: expecting an element
 )(
 ^
+error: expecting an expression
+)(
+  ^
 >>> fun foo() = 98
 >>> foo()
 98