feat: Introduce ToolComponent interface for held item events and update EventListener to dispatch them.

src/main/kotlin/net/hareworks/hcu/items/api/component/ToolComponent.kt

@@ -0,0 +1,9 @@
+package net.hareworks.hcu.items.api.component
+
+import org.bukkit.entity.Player
+import org.bukkit.inventory.ItemStack
+
+interface ToolComponent : CustomComponent {
+    fun onHoldTick(player: Player, item: ItemStack)
+    fun onStopHolding(player: Player, item: ItemStack) {}
+}

src/main/kotlin/net/hareworks/hcu/items/content/components/VeinMinerComponent.kt

@@ -1,6 +1,6 @@
 package net.hareworks.hcu.items.content.components
 
-import net.hareworks.hcu.items.api.component.EquippableComponent
+import net.hareworks.hcu.items.api.component.ToolComponent
 import net.hareworks.hcu.items.api.Tier
 import net.hareworks.hcu.items.config.Config
 import org.bukkit.Material
@@ -25,7 +25,7 @@ import java.util.Queue
 import java.util.Random
 import java.util.UUID
 
-class VeinMinerComponent(private val plugin: JavaPlugin) : EquippableComponent {
+class VeinMinerComponent(private val plugin: JavaPlugin) : ToolComponent {
 
     override val key: NamespacedKey = NamespacedKey(plugin, "vein_miner")
     override val displayName: String = "Vein Miner"
@@ -57,7 +57,7 @@ class VeinMinerComponent(private val plugin: JavaPlugin) : EquippableComponent {
         item.itemMeta = meta
     }
 
-    override fun onTick(player: Player, item: ItemStack) {
+    override fun onHoldTick(player: Player, item: ItemStack) {
         // ハイライト条件チェック (Sneakしながら)
         if (!player.isSneaking) {
             clearHighlight(player)
@@ -117,8 +117,7 @@ class VeinMinerComponent(private val plugin: JavaPlugin) : EquippableComponent {
         activeHighlights[player.uniqueId] = HighlightSession(targetBlock, entities, System.currentTimeMillis())
     }
     
-    // アイテム持ち替えやスニーク解除時にも消えるように
+    override fun onStopHolding(player: Player, item: ItemStack) {
-    override fun onUnequip(player: Player, item: ItemStack) {
         clearHighlight(player)
     }
 

src/main/kotlin/net/hareworks/hcu/items/listeners/EventListener.kt

@@ -11,10 +11,15 @@ import org.bukkit.inventory.EquipmentSlot
 import org.bukkit.inventory.ItemStack
 
 import net.hareworks.hcu.items.api.component.EquippableComponent
+import net.hareworks.hcu.items.api.component.ToolComponent
 import org.bukkit.plugin.Plugin
 
 class EventListener(private val plugin: Plugin) : Listener {
 
+    // Track previously held items for ToolComponents to detect when they stop being held
+    // Key: Player UUID, Value: Pair(MainHandItem, OffHandItem)
+    private val lastHeldItems = java.util.concurrent.ConcurrentHashMap<java.util.UUID, Pair<ItemStack?, ItemStack?>>()
+
     init {
         plugin.server.scheduler.runTaskTimer(plugin, Runnable {
             tickComponents()
@@ -132,14 +137,72 @@ class EventListener(private val plugin: Plugin) : Listener {
 
     private fun tickComponents() {
         for (player in plugin.server.onlinePlayers) {
-            val items = getEquipmentItems(player)
+            val uuid = player.uniqueId
-            for (item in items) {
+            val currentMainHand = player.inventory.itemInMainHand
+            val currentOffHand = player.inventory.itemInOffHand
+
+            // Get previous items
+            val lastItems = lastHeldItems[uuid]
+            val lastMainHand = lastItems?.first
+            val lastOffHand = lastItems?.second
+
+            // Check Main Hand Change
+            if (lastMainHand != null && lastMainHand != currentMainHand) {
+                 dispatchToComponents(lastMainHand) { component ->
+                    if (component is ToolComponent) {
+                         component.onStopHolding(player, lastMainHand)
+                    }
+                 }
+            }
+
+            // Check Off Hand Change
+            if (lastOffHand != null && lastOffHand != currentOffHand) {
+                 dispatchToComponents(lastOffHand) { component ->
+                    if (component is ToolComponent) {
+                         component.onStopHolding(player, lastOffHand)
+                    }
+                 }
+            }
+            
+            // Update Cache
+            lastHeldItems[uuid] = Pair(currentMainHand, currentOffHand)
+
+            // --- Regular Tick Processing ---
+            
+            // Armor Tick
+            val armorItems = player.inventory.armorContents.filterNotNull()
+            for (item in armorItems) {
+                if (item.type.isAir) continue
                 dispatchToComponents(item) { component ->
                     if (component is EquippableComponent) {
                         component.onTick(player, item)
                     }
                 }
             }
+            
+            // ToolComponents in Main Hand
+            if (!currentMainHand.type.isAir) {
+                dispatchToComponents(currentMainHand) { component ->
+                    if (component is ToolComponent) {
+                        component.onHoldTick(player, currentMainHand)
+                    }
+                    if (component is EquippableComponent) {
+                        component.onTick(player, currentMainHand)
+                    }
+                }
+            }
+            
+            // ToolComponents in Off Hand
+            if (!currentOffHand.type.isAir) {
+                dispatchToComponents(currentOffHand) { component ->
+                    if (component is ToolComponent) {
+                        component.onHoldTick(player, currentOffHand)
+                    }
+                    if (component is EquippableComponent) {
+                        component.onTick(player, currentOffHand)
+                    }
+                }
+            }
         }
     }
 

src/main/kotlin/net/hareworks/hcu/items/registry/ComponentRegistry.kt

@@ -3,6 +3,7 @@ package net.hareworks.hcu.items.registry
 import net.hareworks.hcu.items.api.Tier
 import net.hareworks.hcu.items.api.component.CustomComponent
 import net.hareworks.hcu.items.api.component.EquippableComponent
+import net.hareworks.hcu.items.api.component.ToolComponent
 import org.bukkit.inventory.ItemStack
 
 object ComponentRegistry {
@@ -20,6 +21,10 @@ object ComponentRegistry {
         return components.values.filterIsInstance<EquippableComponent>()
     }
 
+    fun getToolComponents(): List<ToolComponent> {
+        return components.values.filterIsInstance<ToolComponent>()
+    }
+
     /**
      * コンポーネントを依存関係を解決しながら適用する
      */