feat(common-enums): add common ValueEnum interface

This interface exposes a common `value` property such that abstractions
can be made on top of this interface, rather than requiring the concrete
enum class.

androidx/common/common-enums/api/common-enums.api

@@ -7,3 +7,6 @@ public abstract class io/github/edricchan03/androidx/common/enums/EnumFromValue
 	public final fun requireValue (Ljava/lang/Object;)Ljava/lang/Enum;
 }
 
+public abstract interface class io/github/edricchan03/androidx/common/enums/ValueEnum {
+	public abstract fun getValue ()Ljava/lang/Object;
+}

androidx/common/common-enums/src/commonMain/kotlin/io/github/edricchan03/androidx/common/enums/ValueEnum.kt

@@ -0,0 +1,14 @@
+package io.github.edricchan03.androidx.common.enums
+
+/**
+ * Interface which [Enum]s should implement to indicate that
+ * they support the [EnumFromValue] specification.
+ * @since 0.2.0
+ */
+public interface ValueEnum<T> {
+    /**
+     * The underlying internal value.
+     * @since 0.2.0
+     */
+    public val value: T
+}