Make annotations-modifiers private and fix some lost usages

It's needed to prevent usages of them as real annotation/type.
But we can't remove them, because currently some modifiers
are artificially resolved as annotations of those classes.

compiler/testData/repl/regressions/kt6843.repl

@@ -1,4 +1,4 @@
->>> @[data] class Person(val name: String)
+>>> data class Person(val name: String)
 >>> var x: String? = "hello"
 >>> val y = x?.let { Person(it) }
 >>> y