feat: handle stacking in inventory and show item count and current/max ammo of ranged weapons

src/engine/world/generator.ts

@@ -52,7 +52,12 @@ export function generateWorld(floor: number, runState: RunState): { world: World
       items: [
         ...runState.inventory.items,
         // Add starting items for testing if empty
-        ...(runState.inventory.items.length === 0 ? [ITEMS["health_potion"], ITEMS["health_potion"], ITEMS["iron_sword"], ITEMS["throwing_dagger"], ITEMS["throwing_dagger"], ITEMS["throwing_dagger"], ITEMS["pistol"]] : [])
+        ...(runState.inventory.items.length === 0 ? [
+          { ...ITEMS["health_potion"], quantity: 2 },
+          ITEMS["iron_sword"],
+          { ...ITEMS["throwing_dagger"], quantity: 3 },
+          ITEMS["pistol"]
+        ] : [])
       ] 
     },
     energy: 0

src/scenes/systems/ItemManager.ts

@@ -66,33 +66,47 @@ export class ItemManager {
 
     if (itemActor) {
       const item = itemActor.item;
-      
+      const result = this.addItem(player, item);
-      // Stacking Logic
-      if (item.stackable) {
-          const existingItem = player.inventory.items.find(it => it.id === item.id);
-          if (existingItem) {
-              existingItem.quantity = (existingItem.quantity || 1) + (item.quantity || 1);
-              console.log(`Stacked ${item.name}. New quantity: ${existingItem.quantity}`);
-              
-              this.entityManager.removeActor(itemActor.id);
-              return existingItem;
-          }
-      }
-
-      // Add to inventory
-      item.quantity = item.quantity || 1;
-      player.inventory.items.push(item);
       
       // Remove from world
       this.entityManager.removeActor(itemActor.id);
       
       console.log("Picked up:", item.name);
-      return item;
+      return result;
     }
 
     return null;
   }
 
+  /**
+   * Add an item to player inventory, handling stacking if applicable
+   * @returns The added or modified item
+   */
+  addItem(player: CombatantActor, item: Item): Item {
+    if (!player.inventory) throw new Error("Player has no inventory");
+
+    // Deep clone item (crucial for items with mutable stats like ammo or when picking up from ground)
+    const itemToAdd = { ...item } as Item;
+    if ('stats' in itemToAdd && itemToAdd.stats) {
+        (itemToAdd as any).stats = { ...itemToAdd.stats }; 
+    }
+
+    // Stacking Logic
+    if (itemToAdd.stackable) {
+        const existingItem = player.inventory.items.find(it => it.id === itemToAdd.id);
+        if (existingItem) {
+            existingItem.quantity = (existingItem.quantity || 1) + (itemToAdd.quantity || 1);
+            console.log(`Stacked ${itemToAdd.name}. New quantity: ${existingItem.quantity}`);
+            return existingItem;
+        }
+    }
+
+    // Add to inventory
+    itemToAdd.quantity = itemToAdd.quantity || 1;
+    player.inventory.items.push(itemToAdd);
+    return itemToAdd;
+  }
+
   /**
    * Handle using an item from inventory
    * Returns information about what happened

src/ui/components/InventoryOverlay.ts

@@ -236,6 +236,26 @@ export class InventoryOverlay extends OverlayComponent {
       sprite.setScale(2.2); // Scale to fit nicely in 44px slots
       
       slot.add(sprite);
+
+      // Add Count Label (Bottom-Right)
+      let labelText = "";
+      if (item.stackable) {
+        labelText = `x${item.quantity || 1}`;
+      } else if (item.type === "Weapon" && item.weaponType === "ranged" && item.stats) {
+        labelText = `${item.stats.currentAmmo}/${item.stats.magazineSize}`;
+      }
+
+      if (labelText) {
+        const slotSize = 44;
+        const display = this.scene.add.text(slotSize / 2 - 3, slotSize / 2 - 3, labelText, {
+          fontSize: "11px",
+          color: "#ffffff",
+          fontStyle: "bold",
+          stroke: "#000000",
+          strokeThickness: 2
+        }).setOrigin(1, 1);
+        slot.add(display);
+      }
       
       // Add interactivity
       slot.setInteractive(new Phaser.Geom.Rectangle(-22, -22, 44, 44), Phaser.Geom.Rectangle.Contains);