Simplify and slightly optimize EntityClassDescriptor

Could probably also be a record, though I'll look into that at another time

src/main/java/carpet/script/api/Entities.java

@@ -244,7 +244,7 @@ public class Entities {
         {
             if (lv.size() > 1) throw new InternalExpressionException("'entity_types' requires one or no arguments");
             String desc = (lv.size() == 1)?lv.get(0).getString():"*";
-            return EntityValue.getEntityDescriptor(desc, ((CarpetContext) c).s.getServer()).listValue;
+            return EntityValue.getEntityDescriptor(desc, ((CarpetContext) c).s.getServer()).listValue();
         });
 
         expression.addContextFunction("entity_load_handler", -1, (c, t, lv) ->
@@ -255,7 +255,7 @@ public class Entities {
                     ? ((ListValue) entityValue).getItems().stream().map(Value::getString).collect(Collectors.toList())
                     : Collections.singletonList(entityValue.getString());
             Set<EntityType<? extends Entity>> types = new HashSet<>();
-            descriptors.forEach(s -> types.addAll(EntityValue.getEntityDescriptor(s, ((CarpetContext) c).s.getServer()).typeList));
+            descriptors.forEach(s -> types.addAll(EntityValue.getEntityDescriptor(s, ((CarpetContext) c).s.getServer()).types));
             FunctionArgument funArg = FunctionArgument.findIn(c, expression.module, lv, 1, true, false);
             CarpetEventServer events = ((CarpetScriptHost)c.host).scriptServer().events;
             if (funArg.function == null)

src/main/java/carpet/script/value/EntityValue.java

@@ -283,29 +283,15 @@ public class EntityValue extends Value
 
     public static class EntityClassDescriptor
     {
-        public EntityTypeTest<Entity, ? extends Entity> directType; // interface of EntityType
+        public final EntityTypeTest<Entity, ? extends Entity> directType; // interface of EntityType
-        public Predicate<? super Entity> filteringPredicate;
+        public final Predicate<? super Entity> filteringPredicate;
-        public List<EntityType<? extends  Entity>> typeList;
+        public final List<EntityType<? extends Entity>> types;
-        public Value listValue;
-        EntityClassDescriptor(EntityType<?> type, Predicate<? super Entity> predicate, List<EntityType<?>> types)
-        {
-            directType = type;
-            filteringPredicate = predicate;
-            typeList = types;
-            listValue = (types==null)?Value.NULL:ListValue.wrap(types.stream().map(et -> StringValue.of(nameFromRegistryId(Registry.ENTITY_TYPE.getKey(et)))).collect(Collectors.toList()));
-        }
 
-        EntityClassDescriptor( EntityTypeTest<Entity, ?> type, Predicate<? super Entity> predicate, List<EntityType<?>> types)
+        EntityClassDescriptor(EntityTypeTest<Entity, ?> type, Predicate<? super Entity> predicate, List<EntityType<?>> types)
         {
-            directType = type;
+            this.directType = type;
-            filteringPredicate = predicate;
+            this.filteringPredicate = predicate;
-            typeList = types;
+            this.types = types;
-            listValue = (types==null)?Value.NULL:ListValue.wrap(types.stream().map(et -> StringValue.of(nameFromRegistryId(Registry.ENTITY_TYPE.getKey(et)))).collect(Collectors.toList()));
-        }
-
-        EntityClassDescriptor(EntityType<?> type, Predicate<? super Entity> predicate, Stream<EntityType<?>> types)
-        {
-            this(type, predicate, types.toList());
         }
 
         EntityClassDescriptor(EntityTypeTest<Entity, ?> type, Predicate<? super Entity> predicate, Stream<EntityType<?>> types)
@@ -313,6 +299,10 @@ public class EntityValue extends Value
             this(type, predicate, types.toList());
         }
 
+        public Value listValue() {
+            return ListValue.wrap(types.stream().map(et -> StringValue.of(nameFromRegistryId(Registry.ENTITY_TYPE.getKey(et)))));
+        }
+
         public final static Map<String, EntityClassDescriptor> byName = new HashMap<>() {{
             List<EntityType<?>> allTypes = Registry.ENTITY_TYPE.stream().toList();
             // nonliving types