feat: add participant data persistence display and mobile responsive fixes

- Add getStats() method to participantService for tag distribution
- Update participants API to return tagDistribution statistics
- Load existing participants on AdminControl mount
- Add mobile responsive styles for import section

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

packages/client-screen/src/views/AdminControl.vue

@@ -128,6 +128,25 @@ const tagLabels: Record<string, string> = {
   'horse': '属马',
 };
 
+// Load existing participants from server
+async function loadParticipants() {
+  try {
+    const response = await fetch('/api/admin/participants');
+    const data = await response.json();
+    if (data.success && data.data?.count > 0) {
+      importResult.value = {
+        success: true,
+        totalCount: data.data.count,
+        importedCount: data.data.count,
+        tagDistribution: data.data.tagDistribution || {},
+        errors: [],
+      };
+    }
+  } catch (error) {
+    console.error('Failed to load participants:', error);
+  }
+}
+
 // Navigation
 function goBack() {
   router.push('/');
@@ -348,6 +367,8 @@ onMounted(() => {
   admin.connect();
   // 加载服务器奖项配置
   loadPrizeConfig();
+  // 加载已导入的参与者数据
+  loadParticipants();
 });
 </script>
 
@@ -1687,13 +1708,13 @@ $admin-danger: #ef4444;
 
 .result-errors {
   margin-top: 12px;
-  
+
   .error-line {
     font-size: 12px;
     color: #ef4444;
     margin-bottom: 4px;
   }
-  
+
   .error-more {
     font-size: 12px;
     color: #888;
@@ -1701,6 +1722,45 @@ $admin-danger: #ef4444;
   }
 }
 
+// Import Section Mobile Styles
+@media (max-width: 768px) {
+  .import-section {
+    grid-column: span 1;
+  }
+
+  .import-controls {
+    flex-direction: column;
+    align-items: stretch;
+    gap: 12px;
+  }
+
+  .file-input-wrapper {
+    width: 100%;
+
+    .file-input-label {
+      width: 100%;
+      text-align: center;
+      box-sizing: border-box;
+    }
+  }
+
+  .result-stats {
+    gap: 12px;
+
+    .stat-item {
+      min-width: calc(33% - 8px);
+
+      .stat-value {
+        font-size: 18px;
+      }
+    }
+  }
+
+  .import-result {
+    padding: 12px;
+  }
+}
+
 // Prize Config Button & Modal
 .prize-config-btn {
   margin-top: 12px;