Used cards: counter quote tag instead of client-temporary feature; item type Material

Client-temporary features are stripped when an item sits on the front
counter, so the scam markup never applied. The quote now lives in a tag and
counts only while the item is not owned. GPU item type ELECTRONIC has no
translation in the game, so cards are typed as Material.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

src/Decentralized/Items.cs

@@ -21,7 +21,7 @@ namespace Decentralized
         public const string FakeTag = "PD_FAKE_OF";
         public const string RefurbTag = "PD_REFURBISHED";
         public const string DeadTag = "PD_DEAD";
-        public const string LookTag = "PD_LOOK", BackTag = "PD_BACK";
+        public const string LookTag = "PD_LOOK", BackTag = "PD_BACK", QuoteTag = "PD_QUOTE";
 
         public static Action OpenTerminal;
 
@@ -69,7 +69,7 @@ namespace Decentralized
         private static GameItem CreateGpu(HardwareSpec spec)
         {
             var item = ItemDirectory.CreateEmptyItem(GpuId(spec.Model));
-            item.SetGameItemType("ELECTRONIC");
+            item.SetGameItemType("MATERIAL");
             item.onLoaded = Refresh;
             // 右键"切换"翻面；外观差异用叠加图画在同一张底图上
             item.EnableTag(ToggleAppearanceHelper.TOGGLE_APPEARANCE_TAG);
@@ -95,6 +95,20 @@ namespace Decentralized
             return item;
         }
 
+        /// <summary>贩子的柜台报价：只在物品还不属于玩家时按报价算，归玩家之后立刻只值真实价值。</summary>
+        public static void SetQuote(GameItem item, long quote)
+        {
+            item.ModifyTag(QuoteTag, t => t.Enable().SetLong(quote));
+            Refresh(item);
+        }
+
+        private static void SyncValue(GameItem item)
+        {
+            if (item.IsTag(DeadTag)) return;
+            long value = item.IsTag(QuoteTag) && !GeneralHelper.IsItemOwned(item) ? item.GetTagReadonly(QuoteTag).GetLong() : CardValue.True(ToUnit(item));
+            if (item.unitValue != value) item.unitValue = value;
+        }
+
         public static Unit ToUnit(GameItem item)
         {
             string model = item.identifier.Substring(GpuPrefix.Length);
@@ -135,6 +149,7 @@ namespace Decentralized
             item.name = L.T("item.gpu.name", label.Brand, DisplayModel(label.Model));
             item.shortDescription = L.T("item.gpu.desc", Fmt.Num(label.DisplayHash), Fmt.Num(label.Kj), Mathf.RoundToInt((float)u.Health));
             item.unitValue = CardValue.True(u);
+            SyncValue(item);
         }
 
         private static Sprite ModSprite(string key)
@@ -147,6 +162,7 @@ namespace Decentralized
         private static List<ItemSpriteModifier> Overlays(GameItem item)
         {
             var list = new List<ItemSpriteModifier>();
+            SyncValue(item);   // 归属变化（买下）后价格随之变回真实价值
             if (item.IsTag(DeadTag)) return list;
             var u = ToUnit(item);
             var keys = new List<string>();