feat(web): cache dashboard aggregations with version invalidation

reaction_board/web/static/index.html

@@ -12,25 +12,38 @@
 </head>
 <body>
   <div class="app" id="app">
-    <header class="topbar">
+    <header class="topbar mobile-topbar">
       <a class="brand" href="/home">
-        <span class="brand-mark">咻</span>
+        <span class="brand-mark">满</span>
         <span class="brand-text">
           <strong>Reaction 看板</strong>
-          <small id="topbar-title">最新动态</small>
+          <small class="brand-subtitle">最新动态</small>
         </span>
       </a>
-      <a class="topbar-hint" id="topbar-auth" href="/login" hidden>登录</a>
-      <span class="topbar-hint" id="topbar-hint" hidden>预览</span>
+      <a class="topbar-hint topbar-auth" href="/login" hidden>登录</a>
+      <span class="topbar-hint topbar-preview" hidden>预览</span>
     </header>
     <div class="preview-banner" id="preview-banner" hidden>预览数据 · 不影响真实数据库</div>
     <main class="main-shell">
       <div id="view"></div>
     </main>
-    <nav class="bottom-nav" id="bottom-nav" aria-label="主导航"></nav>
+    <nav class="bottom-nav" id="bottom-nav" aria-label="主导航">
+      <div class="sidebar-topbar">
+        <a class="brand" href="/home">
+          <span class="brand-mark">满</span>
+          <span class="brand-text">
+            <strong>Reaction 看板</strong>
+            <small class="brand-subtitle">最新动态</small>
+          </span>
+        </a>
+        <a class="topbar-hint topbar-auth" href="/login" hidden>登录</a>
+        <span class="topbar-hint topbar-preview" hidden>预览</span>
+      </div>
+      <div class="nav-items" id="nav-items"></div>
+    </nav>
   </div>
   <div class="toast" id="toast" role="status" aria-live="polite"></div>
   <script src="/static/vendor/echarts.min.js"></script>
   <script type="module" src="/static/app.js"></script>
 </body>
-</html>
+</html>