feat(mining-app): 兑换页面积分股池和已销毁量改为原始数字显示

将"市场数据"中的"积分股池"和"已销毁量"从缩写单位（万/亿）
改为原始十进制数字显示，使用逗号千位分隔符。

- format_utils.dart: 新增 formatWithCommas() 函数，直接显示原始
  数值并用逗号每3位分隔，不再缩写为万/亿
- trading_page.dart: 积分股池和已销毁量两个字段从 formatCompact()
  改为 formatWithCommas()

示例: 52.38亿 → 5,238,000,000

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/mining-app/lib/core/utils/format_utils.dart

@@ -32,6 +32,18 @@ String formatCompact(String? value) {
   }
 }
 
+/// 原始数值 + 逗号千位分隔（不缩写万/亿）
+String formatWithCommas(String? value) {
+  if (value == null || value.isEmpty) return '0';
+  try {
+    final num = double.parse(value);
+    final formatter = NumberFormat('#,##0.########', 'zh_CN');
+    return formatter.format(num);
+  } catch (e) {
+    return '0';
+  }
+}
+
 String formatPercent(String? value, [int precision = 2]) {
   if (value == null || value.isEmpty) return '0%';
   try {

frontend/mining-app/lib/presentation/pages/trading/trading_page.dart

@@ -378,7 +378,7 @@ class _TradingPageState extends ConsumerState<TradingPage> {
             children: [
               _buildMarketDataItem(
                 '积分股池',
-                market != null ? formatCompact(market.greenPoints) : null,
+                market != null ? formatWithCommas(market.greenPoints) : null,
                 _orange,
                 isLoading,
               ),
@@ -386,7 +386,7 @@ class _TradingPageState extends ConsumerState<TradingPage> {
               const SizedBox(width: 16),
               _buildMarketDataItem(
                 '已销毁量',
-                market != null ? formatCompact(market.blackHoleAmount) : null,
+                market != null ? formatWithCommas(market.blackHoleAmount) : null,
                 _red,
                 isLoading,
               ),