Add SimpleNamedDefinition (#267)

Author: WillQizza

bedrock-codec/src/main/java/org/cloudburstmc/protocol/bedrock/data/definitions/SimpleNamedDefinition.java

@@ -0,0 +1,10 @@
+package org.cloudburstmc.protocol.bedrock.data.definitions;
+
+import lombok.Value;
+import org.cloudburstmc.protocol.common.NamedDefinition;
+
+@Value
+public class SimpleNamedDefinition implements NamedDefinition {
+    String identifier;
+    int runtimeId;
+}