Introduce Char.MIN_VALUE and MAX_VALUE constants (KT-21763)

Add Char.MIN_VALUE and Char.MAX_VALUE implementations in primitive companion objects.
Update builtins test data and public API.

Co-authored-by: Oskar Drozda <themppsplx@gmail.com>

libraries/stdlib/js/runtime/primitiveCompanionObjects.kt

@@ -103,6 +103,12 @@ private object ByteCompanionObject {
 
 @JsName("CharCompanionObject")
 private object CharCompanionObject {
+    @JsName("MIN_VALUE")
+    public const val MIN_VALUE: Char = '\u0000'
+
+    @JsName("MAX_VALUE")
+    public const val MAX_VALUE: Char = '\uFFFF'
+
     @JsName("MIN_HIGH_SURROGATE")
     public const val MIN_HIGH_SURROGATE: Char = '\uD800'
 

libraries/stdlib/jvm/runtime/kotlin/jvm/internal/PrimitiveCompanionObjects.kt

@@ -51,6 +51,8 @@ internal object ByteCompanionObject {
 
 
 internal object CharCompanionObject {
+    const val MIN_VALUE: Char = '\u0000'
+    const val MAX_VALUE: Char = '\uFFFF'
     const val MIN_HIGH_SURROGATE: Char = '\uD800'
     const val MAX_HIGH_SURROGATE: Char = '\uDBFF'
     const val MIN_LOW_SURROGATE: Char = '\uDC00'