feat(ui): 사망 화면 잃은 아이템 희귀도 색상 표시

- DeathInfo에 lostItemRarity 필드 추가
- 사망 처리 시 아이템 희귀도 저장
- 사망 오버레이에서 희귀도별 색상 적용
  - Common: 회색, Uncommon: 녹색, Rare: 파랑
  - Epic: 보라, Legendary: 주황

lib/src/core/engine/progress_service.dart

@@ -16,6 +16,7 @@ import 'package:asciineverdie/src/core/model/combat_stats.dart';
 import 'package:asciineverdie/src/core/model/equipment_item.dart';
 import 'package:asciineverdie/src/core/model/equipment_slot.dart';
 import 'package:asciineverdie/src/core/model/game_state.dart';
+import 'package:asciineverdie/src/core/model/item_stats.dart';
 import 'package:asciineverdie/src/core/model/monster_combat_stats.dart';
 import 'package:asciineverdie/src/core/model/monster_grade.dart';
 import 'package:asciineverdie/src/core/model/potion.dart';
@@ -970,6 +971,7 @@ class ProgressService {
     var lostCount = 0;
     String? lostItemName;
     EquipmentSlot? lostItemSlot;
+    ItemRarity? lostItemRarity;
 
     if (!isBossDeath) {
       // 무기(슬롯 0)를 제외한 장착된 장비 중 1개를 제물로 삭제
@@ -999,6 +1001,7 @@ class ProgressService {
         final lostItem = state.equipment.getItemByIndex(sacrificeIndex);
         lostItemName = lostItem.name;
         lostItemSlot = EquipmentSlot.values[sacrificeIndex];
+        lostItemRarity = lostItem.rarity;
 
         // 해당 슬롯을 빈 장비로 교체
         newEquipment = newEquipment.setItemByIndex(
@@ -1015,6 +1018,7 @@ class ProgressService {
       lostEquipmentCount: lostCount,
       lostItemName: lostItemName,
       lostItemSlot: lostItemSlot,
+      lostItemRarity: lostItemRarity,
       goldAtDeath: state.inventory.gold,
       levelAtDeath: state.traits.level,
       timestamp: state.skillSystem.elapsedMs,

lib/src/core/model/game_state.dart

@@ -132,6 +132,7 @@ class DeathInfo {
     required this.timestamp,
     this.lostItemName,
     this.lostItemSlot,
+    this.lostItemRarity,
     this.lastCombatEvents = const [],
   });
 
@@ -150,6 +151,9 @@ class DeathInfo {
   /// 제물로 바친 아이템 슬롯 (null이면 없음)
   final EquipmentSlot? lostItemSlot;
 
+  /// 제물로 바친 아이템 희귀도 (null이면 없음)
+  final ItemRarity? lostItemRarity;
+
   /// 사망 시점 골드
   final int goldAtDeath;
 
@@ -168,6 +172,7 @@ class DeathInfo {
     int? lostEquipmentCount,
     String? lostItemName,
     EquipmentSlot? lostItemSlot,
+    ItemRarity? lostItemRarity,
     int? goldAtDeath,
     int? levelAtDeath,
     int? timestamp,
@@ -179,6 +184,7 @@ class DeathInfo {
       lostEquipmentCount: lostEquipmentCount ?? this.lostEquipmentCount,
       lostItemName: lostItemName ?? this.lostItemName,
       lostItemSlot: lostItemSlot ?? this.lostItemSlot,
+      lostItemRarity: lostItemRarity ?? this.lostItemRarity,
       goldAtDeath: goldAtDeath ?? this.goldAtDeath,
       levelAtDeath: levelAtDeath ?? this.levelAtDeath,
       timestamp: timestamp ?? this.timestamp,

lib/src/features/game/widgets/death_overlay.dart

@@ -5,6 +5,7 @@ import 'package:asciineverdie/src/core/l10n/game_data_l10n.dart';
 import 'package:asciineverdie/src/core/model/combat_event.dart';
 import 'package:asciineverdie/src/core/model/equipment_slot.dart';
 import 'package:asciineverdie/src/core/model/game_state.dart';
+import 'package:asciineverdie/src/core/model/item_stats.dart';
 import 'package:asciineverdie/src/shared/retro_colors.dart';
 
 /// 사망 오버레이 위젯 (Phase 4)
@@ -294,10 +295,8 @@ class DeathOverlay extends StatelessWidget {
     final expColor = RetroColors.expOf(context);
     final gold = RetroColors.goldOf(context);
 
-    // 슬롯명 + 아이템명 조합
-    final lostItemDisplay = hasLostItem
-        ? '[${_getSlotName(deathInfo.lostItemSlot)}] ${deathInfo.lostItemName}'
-        : null;
+    // 희귀도에 따른 아이템 이름 색상
+    final itemRarityColor = _getRarityColor(deathInfo.lostItemRarity);
 
     return Column(
       children: [
@@ -326,12 +325,23 @@ class DeathOverlay extends StatelessWidget {
                         ),
                       ),
                       const SizedBox(height: 4),
-                      Text(
-                        lostItemDisplay!,
-                        style: TextStyle(
+                      // 슬롯명 (회색) + 아이템명 (희귀도 색상)
+                      Text.rich(
+                        TextSpan(
+                          children: [
+                            TextSpan(
+                              text: '[${_getSlotName(deathInfo.lostItemSlot)}] ',
+                              style: TextStyle(color: muted),
+                            ),
+                            TextSpan(
+                              text: deathInfo.lostItemName!,
+                              style: TextStyle(color: itemRarityColor),
+                            ),
+                          ],
+                        ),
+                        style: const TextStyle(
                           fontFamily: 'PressStart2P',
                           fontSize: 13,
-                          color: hpColor,
                         ),
                       ),
                     ],
@@ -695,4 +705,16 @@ class DeathOverlay extends StatelessWidget {
       EquipmentSlot.sollerets => l10n.slotSollerets,
     };
   }
+
+  /// 희귀도에 따른 색상 반환
+  Color _getRarityColor(ItemRarity? rarity) {
+    if (rarity == null) return Colors.grey;
+    return switch (rarity) {
+      ItemRarity.common => Colors.grey,
+      ItemRarity.uncommon => Colors.green,
+      ItemRarity.rare => Colors.blue,
+      ItemRarity.epic => Colors.purple,
+      ItemRarity.legendary => Colors.orange,
+    };
+  }
 }