fix(ui): 修改提取相关文字

- 兑换页面：'提取 / 转动' → '提取'
- 提款页面：'提款 积分' → '提取积分'

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

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

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

@@ -263,7 +263,7 @@ class _TradingPageState extends ConsumerState<TradingPage> {
                 // // 分隔线
                 // _buildDivider(),
                 const SizedBox(height: 24),
-                // 提取/转动按钮
+                // 提取按钮
                 _buildWithdrawButton(),
                 const SizedBox(height: 8),
                 // USDT余额显示
@@ -520,7 +520,7 @@ class _TradingPageState extends ConsumerState<TradingPage> {
           );
   }
 
-  /// 构建提取/转动按钮
+  /// 构建提取按钮
   /// 当 USDT 余额为 0 时禁用
   Widget _buildWithdrawButton() {
     // 余额为0时禁用
@@ -562,7 +562,7 @@ class _TradingPageState extends ConsumerState<TradingPage> {
                 ),
                 const SizedBox(width: 8),
                 Text(
-                  '提取 / 转动',
+                  '提取',
                   style: TextStyle(
                     fontSize: 16,
                     fontFamily: 'Inter',

frontend/mobile-app/lib/features/withdraw/presentation/pages/withdraw_usdt_page.dart

@@ -365,7 +365,7 @@ class _WithdrawUsdtPageState extends ConsumerState<WithdrawUsdtPage> {
           // 标题
           const Expanded(
             child: Text(
-              '提款 积分',
+              '提取积分',
               style: TextStyle(
                 fontSize: 18,
                 fontFamily: 'Inter',