feat(web): cache dashboard aggregations with version invalidation

reaction_board/web/static/views/rankings.js

@@ -126,10 +126,7 @@ export async function renderRankings(root, { query }) {
 
   root.innerHTML = `<section class="page rankings-page">
     <header class="page-head">
-      <div>
-        <h1>榜单</h1>
-        <p class="page-sub">共 ${formatCount(data.total)} ${scope === "up" ? "个 UP" : "条视频"}</p>
-      </div>
+      <h1>榜单 <span class="page-sub">共 ${formatCount(data.total)} ${scope === "up" ? "个 UP" : "条视频"}</span></h1>
     </header>
     ${controls({ scope, sort, within, growthDays, q, folder, minVideos, folders })}
     ${data.available === false ? `<div class="notice-row warning">