small nullpointer fix in EntityGadget, in case meta gadget is not set

src/main/java/emu/grasscutter/game/entity/EntityGadget.java

@@ -219,9 +219,12 @@ public class EntityGadget extends EntityBaseGadget {
                 .setConfigId(this.getConfigId())
                 .setGadgetState(this.getState())
                 .setIsEnableInteract(true)
-                .setDraftId(this.metaGadget.draft_id)
                 .setAuthorityPeerId(this.getScene().getWorld().getHostPeerId());
 
+        if(this.metaGadget != null) {
+            gadgetInfo.setDraftId(this.metaGadget.draft_id);
+        }
+
         if (this.getContent() != null) {
             this.getContent().onBuildProto(gadgetInfo);
         }