ucs: lch: Reduce garbage objects created for conversions

Triple requires boxing, while DoubleArray allows keeping everything
primitive.
diff --git a/src/commonMain/kotlin/dev/kdrag0n/colorkt/ucs/polar/Lch.kt b/src/commonMain/kotlin/dev/kdrag0n/colorkt/ucs/polar/Lch.kt
index 1646966..36f21fb 100644
--- a/src/commonMain/kotlin/dev/kdrag0n/colorkt/ucs/polar/Lch.kt
+++ b/src/commonMain/kotlin/dev/kdrag0n/colorkt/ucs/polar/Lch.kt
@@ -33,10 +33,10 @@
     val h: Double
 
     companion object {
-        internal fun Lab.toLch(): Triple<Double, Double, Double> {
+        internal fun Lab.toLch(): DoubleArray {
             val hDeg = atan2(b, a).toDegrees()
 
-            return Triple(
+            return doubleArrayOf(
                 L,
                 sqrt(a.pow(2) + b.pow(2)),
                 // Normalize the angle, as many will be negative
@@ -44,10 +44,10 @@
             )
         }
 
-        internal fun Lch.toLab(): Triple<Double, Double, Double> {
+        internal fun Lch.toLab(): DoubleArray {
             val hRad = h.toRadians()
 
-            return Triple(
+            return doubleArrayOf(
                 L,
                 C * cos(hRad),
                 C * sin(hRad),