feat(ops): 限制并发卡片最多显示3组数据，超出可滚动

frontend/src/views/admin/ops/components/OpsConcurrencyCard.vue

@@ -343,7 +343,7 @@ watch(realtimeEnabled, async (enabled) => {
       </div>
 
       <!-- 汇总视图（平台/分组） -->
-      <div v-else-if="displayDimension !== 'account'" class="custom-scrollbar flex-1 space-y-2 overflow-y-auto p-3">
+      <div v-else-if="displayDimension !== 'account'" class="custom-scrollbar max-h-[360px] flex-1 space-y-2 overflow-y-auto p-3">
         <div v-for="row in (displayRows as SummaryRow[])" :key="row.key" class="rounded-lg bg-gray-50 p-3 dark:bg-dark-900">
           <!-- 标题行 -->
           <div class="mb-2 flex items-center justify-between gap-2">
@@ -417,7 +417,7 @@ watch(realtimeEnabled, async (enabled) => {
       </div>
 
       <!-- 账号详细视图 -->
-      <div v-else class="custom-scrollbar flex-1 space-y-2 overflow-y-auto p-3">
+      <div v-else class="custom-scrollbar max-h-[360px] flex-1 space-y-2 overflow-y-auto p-3">
         <div v-for="row in (displayRows as AccountRow[])" :key="row.key" class="rounded-lg bg-gray-50 p-2.5 dark:bg-dark-900">
           <!-- 账号名称和并发 -->
           <div class="mb-1.5 flex items-center justify-between gap-2">