Stabilize unsigned types KT-45653

Deprecate specialized unsigned iterators for removal.

Fix compiler tests:
- drop unsignedLiteralsOn1_2 because apiVersion 1.2 is no longer supported
- drop experimental unsigned literals diagnostic test

libraries/stdlib/common/src/generated/_Strings.kt

@@ -2087,11 +2087,11 @@ public inline fun CharSequence.sumOf(selector: (Char) -> Long): Long {
 /**
  * Returns the sum of all values produced by [selector] function applied to each character in the char sequence.
  */
-@SinceKotlin("1.4")
+@SinceKotlin("1.5")
 @OptIn(kotlin.experimental.ExperimentalTypeInference::class)
 @OverloadResolutionByLambdaReturnType
 @kotlin.jvm.JvmName("sumOfUInt")
-@ExperimentalUnsignedTypes
+@WasExperimental(ExperimentalUnsignedTypes::class)
 @kotlin.internal.InlineOnly
 public inline fun CharSequence.sumOf(selector: (Char) -> UInt): UInt {
     var sum: UInt = 0.toUInt()
@@ -2104,11 +2104,11 @@ public inline fun CharSequence.sumOf(selector: (Char) -> UInt): UInt {
 /**
  * Returns the sum of all values produced by [selector] function applied to each character in the char sequence.
  */
-@SinceKotlin("1.4")
+@SinceKotlin("1.5")
 @OptIn(kotlin.experimental.ExperimentalTypeInference::class)
 @OverloadResolutionByLambdaReturnType
 @kotlin.jvm.JvmName("sumOfULong")
-@ExperimentalUnsignedTypes
+@WasExperimental(ExperimentalUnsignedTypes::class)
 @kotlin.internal.InlineOnly
 public inline fun CharSequence.sumOf(selector: (Char) -> ULong): ULong {
     var sum: ULong = 0.toULong()