refactor(ui): 위젯 분리 및 화면 개선

- game_play_screen에서 desktop 패널 위젯 분리
- death_overlay에서 death_buttons, death_combat_log 분리
- mobile_carousel_layout에서 mobile_options_menu 분리
- 아레나 위젯 개선 (arena_hp_bar, result_panel 등)
- settings_screen에서 retro_settings_widgets 분리
- 기타 위젯 리팩토링 및 import 경로 업데이트

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

@@ -0,0 +1,168 @@
+import 'package:flutter/material.dart';
+
+import 'package:asciineverdie/data/game_text_l10n.dart' as game_l10n;
+import 'package:asciineverdie/l10n/app_localizations.dart';
+import 'package:asciineverdie/src/shared/l10n/game_data_l10n.dart';
+import 'package:asciineverdie/src/core/model/game_state.dart';
+import 'package:asciineverdie/src/core/model/inventory.dart';
+import 'package:asciineverdie/src/features/game/widgets/combat_log.dart';
+import 'package:asciineverdie/src/features/game/widgets/desktop_panel_widgets.dart';
+import 'package:asciineverdie/src/features/game/widgets/equipment_stats_panel.dart';
+import 'package:asciineverdie/src/features/game/widgets/potion_inventory_panel.dart';
+import 'package:asciineverdie/src/shared/retro_colors.dart';
+
+/// 데스크톱 중앙 패널: Equipment/Inventory
+///
+/// Equipment, Inventory, Potions, Encumbrance, Combat Log 표시
+class DesktopEquipmentPanel extends StatelessWidget {
+  const DesktopEquipmentPanel({
+    super.key,
+    required this.state,
+    required this.combatLogEntries,
+  });
+
+  final GameState state;
+  final List<CombatLogEntry> combatLogEntries;
+
+  @override
+  Widget build(BuildContext context) {
+    final l10n = L10n.of(context);
+    return Card(
+      margin: const EdgeInsets.all(4),
+      color: RetroColors.panelBg,
+      shape: RoundedRectangleBorder(
+        side: const BorderSide(
+          color: RetroColors.panelBorderOuter,
+          width: 2,
+        ),
+        borderRadius: BorderRadius.circular(0),
+      ),
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.stretch,
+        children: [
+          DesktopPanelHeader(title: l10n.equipment),
+          Expanded(
+            flex: 2,
+            child: EquipmentStatsPanel(equipment: state.equipment),
+          ),
+          DesktopPanelHeader(title: l10n.inventory),
+          Expanded(child: _InventoryList(state: state)),
+          DesktopSectionHeader(title: game_l10n.uiPotions),
+          Expanded(
+            child: PotionInventoryPanel(inventory: state.potionInventory),
+          ),
+          DesktopSectionHeader(title: l10n.encumbrance),
+          DesktopSegmentProgressBar(
+            position: state.progress.encumbrance.position,
+            max: state.progress.encumbrance.max,
+            color: Colors.orange,
+          ),
+          DesktopPanelHeader(title: l10n.combatLog),
+          Expanded(flex: 2, child: CombatLog(entries: combatLogEntries)),
+        ],
+      ),
+    );
+  }
+}
+
+/// 인벤토리 목록 위젯
+class _InventoryList extends StatelessWidget {
+  const _InventoryList({required this.state});
+
+  final GameState state;
+
+  @override
+  Widget build(BuildContext context) {
+    final l10n = L10n.of(context);
+    if (state.inventory.items.isEmpty) {
+      return Center(
+        child: Text(
+          l10n.goldAmount(state.inventory.gold),
+          style: const TextStyle(
+            fontFamily: 'PressStart2P',
+            fontSize: 14,
+            color: RetroColors.gold,
+          ),
+        ),
+      );
+    }
+
+    return ListView.builder(
+      itemCount: state.inventory.items.length + 1,
+      padding: const EdgeInsets.symmetric(horizontal: 8),
+      itemBuilder: (context, index) {
+        if (index == 0) {
+          return _buildGoldRow(l10n);
+        }
+        return _buildItemRow(context, state.inventory.items[index - 1]);
+      },
+    );
+  }
+
+  Widget _buildGoldRow(L10n l10n) {
+    return Padding(
+      padding: const EdgeInsets.symmetric(vertical: 2),
+      child: Row(
+        children: [
+          const Icon(
+            Icons.monetization_on,
+            size: 10,
+            color: RetroColors.gold,
+          ),
+          const SizedBox(width: 4),
+          Expanded(
+            child: Text(
+              l10n.gold.toUpperCase(),
+              style: const TextStyle(
+                fontFamily: 'PressStart2P',
+                fontSize: 13,
+                color: RetroColors.gold,
+              ),
+            ),
+          ),
+          Text(
+            '${state.inventory.gold}',
+            style: const TextStyle(
+              fontFamily: 'PressStart2P',
+              fontSize: 14,
+              color: RetroColors.gold,
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+
+  Widget _buildItemRow(BuildContext context, InventoryEntry item) {
+    final translatedName = GameDataL10n.translateItemString(
+      context,
+      item.name,
+    );
+    return Padding(
+      padding: const EdgeInsets.symmetric(vertical: 1),
+      child: Row(
+        children: [
+          Expanded(
+            child: Text(
+              translatedName,
+              style: const TextStyle(
+                fontFamily: 'PressStart2P',
+                fontSize: 13,
+                color: RetroColors.textLight,
+              ),
+              overflow: TextOverflow.ellipsis,
+            ),
+          ),
+          Text(
+            '${item.count}',
+            style: const TextStyle(
+              fontFamily: 'PressStart2P',
+              fontSize: 13,
+              color: RetroColors.cream,
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+}