feat: refine task and countdown interactions

frontend/src/MemoPanel.vue

@@ -211,7 +211,7 @@ defineExpose({ createMemo, requestClose: () => editor.value?.requestClose(), dir
     <div class="memo-panel__main" :inert="selected && mobileDetail ? true : undefined">
       <div class="memo-toolbar">
         <div class="memo-scope" role="tablist" aria-label="备忘录范围"><button role="tab" data-scope="active" :aria-selected="scope==='active'" @click="setScope('active')">活动</button><button role="tab" data-scope="trash" :aria-selected="scope==='trash'" @click="setScope('trash')"><Archive/>回收站</button></div>
-        <button ref="searchToggle" class="memo-search-toggle" type="button" aria-label="展开搜索备忘录" :aria-expanded="mobileLayout ? mobileSearchOpen : true" aria-controls="memo-search-panel" @click="mobileSearchOpen ? closeMobileSearch() : openMobileSearch()"><Search/></button>
+        <button ref="searchToggle" class="memo-search-toggle" type="button" :aria-label="mobileSearchOpen ? '收起搜索备忘录' : '展开搜索备忘录'" :aria-expanded="mobileLayout ? mobileSearchOpen : true" aria-controls="memo-search-panel" @click="mobileSearchOpen ? closeMobileSearch() : openMobileSearch()"><Search/></button>
         <div id="memo-search-panel" class="memo-search-panel" :class="{'is-open':mobileSearchOpen}" :hidden="mobileLayout && !mobileSearchOpen"><label class="memo-search"><Search/><input id="memo-search-input" ref="searchInput" v-model="query" aria-label="搜索备忘录" placeholder="搜索标题或正文…" @keydown="handleSearchKeydown"></label><button v-if="query" type="button" class="memo-search-clear" aria-label="清空搜索" @click="clearSearch"><X/></button></div>
       </div>
       <p v-if="error" class="memo-error" role="alert">{{error}} <button class="link" @click="load()">重试</button></p>