Fixed native POI ownership

- Native structure POI changes persist dirty chunk sections before deferred updates
- Chunk load reconciles final POI states on the owning thread
- Matching POI records retain claimed tickets
- Native flag detection keeps unsupported server behavior intact
- Regression tests cover persistence and failed repair retries

core/src/main/java/art/arcane/iris/core/nms/INMSBinding.java

@@ -245,6 +245,9 @@ public interface INMSBinding {
     default void flushChunkIO(World world) {
     }
 
+    default void reconcileNativeStructurePois(Chunk chunk) {
+    }
+
     void injectBiomesFromMantle(Chunk e, Mantle<Matter> mantle);
 
     ItemStack applyCustomNbt(ItemStack itemStack, KMap<String, Object> customNbt) throws IllegalArgumentException;

core/src/main/java/art/arcane/iris/engine/IrisWorldManager.java

@@ -20,6 +20,7 @@ package art.arcane.iris.engine;
 
 import art.arcane.iris.platform.bukkit.BukkitWorldBinding;
 import art.arcane.iris.core.IrisSettings;
+import art.arcane.iris.core.nms.INMS;
 import art.arcane.iris.engine.data.cache.Cache;
 import art.arcane.iris.engine.framework.Engine;
 import art.arcane.iris.engine.framework.EngineAssignedWorldManager;
@@ -212,6 +213,8 @@ public class IrisWorldManager extends EngineAssignedWorldManager {
             return;
         }
 
+        INMS.get().reconcileNativeStructurePois(e);
+
         if (cleanupServiceStopped || cleanupService == null || cleanupService.isShutdown()) {
             return;
         }