[IR BE] Refactored FoldConstantLowering

- Fix `toString` evaluation for unsigned types in FoldConstantLowering
 - make corner cases around float/double evaluation work for K/JS
 - remove usage of kotlin type

compiler/testData/codegen/box/constants/float.kt

@@ -1,3 +1,16 @@
+// KJS_WITH_FULL_RUNTIME
+// WITH_RUNTIME
+// IGNORE_BACKEND_FIR: JVM_IR
+
+import kotlin.math.*
+
+fun almostEqual(a: Float, b: Float): Boolean = abs(a - b) < 0.0000001F
+
+val umax = UInt.MAX_VALUE
+val ulmax = ULong.MAX_VALUE
+val imax = Int.MAX_VALUE
+val lmax = Long.MAX_VALUE
+
 fun box(): String {
     if (1F != 1.toFloat()) return "fail 1"
     if (1.0F != 1.0.toFloat()) return "fail 2"
@@ -13,6 +26,15 @@ fun box(): String {
     if (1e-1f != 1e-1.toFloat()) return "fail 11"
     if (1.0e-1f != 1.0e-1.toFloat()) return "fail 12"
 
-    return "OK"
-}
+    if (!almostEqual(kotlin.math.E.toFloat(), exp(1.0F))) return "fail 13"
 
+    if (2147483647.toFloat() != imax.toFloat()) return "fail 14"
+
+    if (9223372036854775807L.toFloat() != lmax.toFloat()) return "fail 15"
+
+    if (0xFFFF_FFFF.toFloat() != umax.toFloat()) return "fail 16"
+
+    if ((2.0f * Long.MAX_VALUE + 1) != ulmax.toFloat()) return "fail 17"
+
+    return "OK"
+}

compiler/testData/codegen/box/intrinsics/tostring.kt

@@ -1,7 +1,6 @@
 // IGNORE_BACKEND_FIR: JVM_IR
 // TODO: muted automatically, investigate should it be ran for JS or not
 // IGNORE_BACKEND: JS
-// IGNORE_BACKEND: JS_IR
 
 fun box(): String {
     if (239.toByte().toString() != (239.toByte() as Byte?).toString()) return "byte failed"

compiler/testData/codegen/box/primitiveTypes/kt2269.kt

@@ -1,4 +1,4 @@
-// IGNORE_BACKEND_FIR: JVM_IR
+
 fun box() : String {
     230?.toByte()?.hashCode()
     9.hashCode()