feat(web): refresh palette, simplify ranking toolbar and drop export

reaction_board/web/static/views/candidates.js

@@ -49,10 +49,10 @@ export async function renderCandidates(root) {
       </div>
     </header>
 
-    <div class="notice-row">
-      <strong>Web 看板只读</strong>
-      <span>${data.telegram_enabled ? "请在 Telegram 消息中处理候选。" : "Telegram 未启用，请使用 CLI 或数据库处理候选。"}</span>
-    </div>
+    ${data.items.length ? `<div class="notice-row">
+      <strong>候选处理</strong>
+      <span>${data.telegram_enabled ? "请在 Telegram 消息中收藏、忽略或拉黑。" : "Telegram 未启用，请使用 CLI 或数据库处理候选。"}</span>
+    </div>` : ""}
 
     <section class="panel">
       ${sectionHeader("待确认")}