chore(nav): 暂时隐藏矿机Tab

- 底部导航从4个减少到3个: 龙虎榜、交易、我
- 保留矿机相关代码注释，方便后续恢复
- 调整索引映射以匹配新的Tab顺序

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

frontend/mobile-app/lib/features/home/presentation/pages/home_shell_page.dart

@@ -60,25 +60,27 @@ class _HomeShellPageState extends ConsumerState<HomeShellPage>
 
   int _getCurrentIndex(BuildContext context) {
     final location = GoRouterState.of(context).uri.path;
+    // 矿机Tab暂时隐藏，索引调整为: 0-龙虎榜, 1-交易, 2-我
     if (location.startsWith(RoutePaths.ranking)) return 0;
-    if (location.startsWith(RoutePaths.mining)) return 1;
+    // if (location.startsWith(RoutePaths.mining)) return 1;  // 矿机暂时隐藏
-    if (location.startsWith(RoutePaths.trading)) return 2;
+    if (location.startsWith(RoutePaths.trading)) return 1;
-    if (location.startsWith(RoutePaths.profile)) return 3;
+    if (location.startsWith(RoutePaths.profile)) return 2;
     return 0;
   }
 
   void _onTabTapped(BuildContext context, int index) {
+    // 矿机Tab暂时隐藏，索引调整为: 0-龙虎榜, 1-交易, 2-我
     switch (index) {
       case 0:
         context.go(RoutePaths.ranking);
         break;
+      // case 1:  // 矿机暂时隐藏
+      //   context.go(RoutePaths.mining);
+      //   break;
       case 1:
-        context.go(RoutePaths.mining);
-        break;
-      case 2:
         context.go(RoutePaths.trading);
         break;
-      case 3:
+      case 2:
         context.go(RoutePaths.profile);
         break;
     }

frontend/mobile-app/lib/features/home/presentation/widgets/bottom_nav_bar.dart

@@ -1,7 +1,8 @@
 import 'package:flutter/material.dart';
 
 /// 底部导航栏组件
-/// 包含四个Tab：龙虎榜、矿机、交易、我
+/// 包含三个Tab：龙虎榜、交易、我
+/// 注意：矿机Tab暂时隐藏（未删除代码，方便后续恢复）
 /// 自定义设计风格，使用 LayoutBuilder 确保自适应
 class BottomNavBar extends StatelessWidget {
   final int currentIndex;
@@ -41,20 +42,21 @@ class BottomNavBar extends StatelessWidget {
               activeIcon: Icons.leaderboard,
               label: '龙虎榜',
             ),
+            // 矿机Tab暂时隐藏，保留代码方便后续恢复
+            // _buildNavItem(
+            //   index: 1,
+            //   icon: Icons.memory_outlined,
+            //   activeIcon: Icons.memory,
+            //   label: '矿机',
+            // ),
             _buildNavItem(
-              index: 1,
+              index: 1,  // 原 index: 2
-              icon: Icons.memory_outlined,
-              activeIcon: Icons.memory,
-              label: '矿机',
-            ),
-            _buildNavItem(
-              index: 2,
               icon: Icons.swap_horiz_outlined,
               activeIcon: Icons.swap_horiz,
               label: '交易',
             ),
             _buildNavItem(
-              index: 3,
+              index: 2,  // 原 index: 3
               icon: Icons.person_outline,
               activeIcon: Icons.person,
               label: '我',