fix(profile): 修复伞下树图居中问题；更名提款/转账为提取/转动

- 使用 LayoutBuilder 获取实际容器宽度计算节点显示
- 修改兑换页面按钮文字从"提款/转账"改为"提取/转动"

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

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

frontend/mobile-app/lib/features/profile/presentation/widgets/team_tree_widget.dart

@@ -79,19 +79,22 @@ class _TeamTreeWidgetState extends State<TeamTreeWidget> {
   static const double nodeHorizontalSpacing = 12.0;
   static const double nodeVerticalSpacing = 40.0;
 
+  // 当前容器宽度（由 LayoutBuilder 传递）
+  double _containerWidth = 0;
+
   @override
   Widget build(BuildContext context) {
     return LayoutBuilder(
       builder: (context, constraints) {
         // 使用实际容器宽度而不是屏幕宽度
-        final containerWidth = constraints.maxWidth;
+        _containerWidth = constraints.maxWidth;
 
         return SingleChildScrollView(
           scrollDirection: Axis.horizontal,
           child: SingleChildScrollView(
             child: ConstrainedBox(
               constraints: BoxConstraints(
-                minWidth: containerWidth,
+                minWidth: _containerWidth,
               ),
               child: Center(
                 child: Padding(
@@ -110,9 +113,9 @@ class _TeamTreeWidgetState extends State<TeamTreeWidget> {
   Widget _buildTreeLevel(List<TeamTreeNode> nodes, int level) {
     if (nodes.isEmpty) return const SizedBox.shrink();
 
-    // 计算屏幕可以显示的最大节点数
-    final screenWidth = MediaQuery.of(context).size.width - 32; // 减去左右padding
-    final maxVisibleNodes = ((screenWidth + nodeHorizontalSpacing) / (nodeWidth + nodeHorizontalSpacing)).floor();
+    // 使用容器实际宽度计算最大节点数（减去 padding）
+    final availableWidth = _containerWidth - 16; // 减去左右 padding (8*2)
+    final maxVisibleNodes = ((availableWidth + nodeHorizontalSpacing) / (nodeWidth + nodeHorizontalSpacing)).floor().clamp(1, 100);
 
     // 分离需要显示的节点和隐藏的节点
     List<TeamTreeNode> visibleNodes;

frontend/mobile-app/lib/features/trading/presentation/pages/trading_page.dart

@@ -262,7 +262,7 @@ class _TradingPageState extends ConsumerState<TradingPage> {
                 // 分隔线
                 _buildDivider(),
                 const SizedBox(height: 24),
-                // 提款/转账按钮
+                // 提取/转动按钮
                 _buildWithdrawButton(),
                 const SizedBox(height: 8),
                 // USDT余额显示
@@ -518,7 +518,7 @@ class _TradingPageState extends ConsumerState<TradingPage> {
           );
   }
 
-  /// 构建提款/转账按钮
+  /// 构建提取/转动按钮
   /// 当 USDT 余额为 0 时禁用
   Widget _buildWithdrawButton() {
     // 余额为0时禁用
@@ -560,7 +560,7 @@ class _TradingPageState extends ConsumerState<TradingPage> {
                 ),
                 const SizedBox(width: 8),
                 Text(
-                  '提款 / 转账',
+                  '提取 / 转动',
                   style: TextStyle(
                     fontSize: 16,
                     fontFamily: 'Inter',