refactor(frontend): 重构站点数据面板与签到组件

将原有的站点统计卡片重构为bento布局样式，把签到组件内嵌到站点数据面板中，统一UI风格并简化代码结构

frontend/app/globals.css

@@ -605,6 +605,101 @@ h1, h2, h3, h4 {
     white-space: nowrap;
   }
 
+  /* 站点数据 bento 统计瓦片 */
+  .j13-pulse {
+    display: grid;
+    grid-template-columns: 1fr 1fr;
+    gap: 8px;
+  }
+  .j13-pulse-cell {
+    min-width: 0;
+    padding: 11px 12px 10px;
+    background: var(--panel-2);
+    border: 1px solid var(--line);
+    border-radius: var(--r-sm);
+  }
+  .j13-pulse-lab {
+    display: flex;
+    align-items: center;
+    gap: 5px;
+    font-size: 11.5px;
+    color: var(--ink-3);
+    white-space: nowrap;
+  }
+  .j13-pulse-num {
+    margin-top: 6px;
+    font-size: 21px;
+    font-weight: 800;
+    line-height: 1.05;
+    letter-spacing: -0.015em;
+    color: var(--ink);
+    font-variant-numeric: tabular-nums;
+  }
+  .j13-pulse-foot {
+    display: flex;
+    align-items: center;
+    gap: 3px;
+    margin-top: 6px;
+    font-size: 10.5px;
+    line-height: 1;
+    color: var(--ink-3);
+    font-variant-numeric: tabular-nums;
+    white-space: nowrap;
+  }
+  .j13-pulse-foot.is-up {
+    color: var(--ok);
+    font-weight: 600;
+  }
+  .j13-pulse-dot {
+    position: relative;
+    width: 6px;
+    height: 6px;
+    border-radius: 9999px;
+    background: var(--ok);
+    flex-shrink: 0;
+  }
+  .j13-pulse-dot::after {
+    content: "";
+    position: absolute;
+    inset: -3px;
+    border-radius: 9999px;
+    background: var(--ok);
+    opacity: 0.4;
+    animation: j13-ping 1.8s cubic-bezier(0, 0, 0.2, 1) infinite;
+  }
+  @keyframes j13-ping {
+    0% { transform: scale(0.6); opacity: 0.5; }
+    70%, 100% { transform: scale(1.9); opacity: 0; }
+  }
+  @media (prefers-reduced-motion: reduce) {
+    .j13-pulse-dot::after {
+      animation: none;
+      opacity: 0.25;
+    }
+  }
+  /* 卡内签到条：分隔线 + 紧凑按钮 */
+  .j13-pulse-checkin {
+    margin-top: 10px;
+    padding-top: 11px;
+    border-top: 1px solid var(--line);
+  }
+  .j13-pulse-checkin-btn {
+    gap: 4px;
+    padding: 6px 11px;
+    font-size: 12px;
+    white-space: nowrap;
+  }
+  .j13-pulse-checkin-done {
+    display: inline-flex;
+    align-items: center;
+    gap: 4px;
+    padding: 6px 11px;
+    border-radius: 9999px;
+    font-size: 12px;
+    font-weight: 600;
+    white-space: nowrap;
+  }
+
   /* 热门榜单 */
   .j13-rank {
     position: relative;

frontend/app/page.tsx

@@ -201,6 +201,7 @@ export default async function HomePage({ searchParams }: HomePageProps) {
       {overview && (
         <div className="mt-6">
           <CommunityPanelsMobile
+            stats={overview.stats}
             hot={overview.hot}
             activeUsers={overview.active_users}
             announcements={overview.announcements}