[CMM] Implement Nyxborn Behemoth (#10670)

* [CMM] Implement Nyxborn Behemoth

Regroup the different dynamic values for "total mana value of [FILTER]" under a shared class.

* refactor hints inside TotalPermanentsManaValue

* apply review on TotalPermanentsManaValue->copy

Mage/src/main/java/mage/abilities/hint/ValueHint.java

@@ -28,7 +28,7 @@ public class ValueHint implements Hint {
     }
 
     @Override
-    public Hint copy() {
+    public ValueHint copy() {
         return new ValueHint(this);
     }
 }