style: simplify mobile task views

frontend/src/App.vue

@@ -1523,7 +1523,7 @@ onUnmounted(() => {
             <button v-if="taskReorderMode" class="drag-handle task-drag-handle" :disabled="Boolean(query) || totalPages > 1" aria-label="上下拖动任务排序" title="上下拖动排序" @pointerdown.stop="startTaskReorder(node.task, $event)" @pointermove.stop="moveTaskReorder(node.task, $event)" @pointerup.stop="finishTaskReorder(node.task, $event)" @pointercancel.stop="cancelTaskReorder"><GripVertical/></button>
             <button v-if="activeView!=='trash'" class="task-check" :aria-label="node.task.completed ? `重新打开${node.task.title}` : `完成${node.task.title}`" :aria-pressed="node.task.completed" @click.stop="toggle(node.task)"><span class="task-check-mark" :class="`p${node.task.priority}`"><Check v-if="node.task.completed" /></span></button>
             <div class="task-main" role="button" tabindex="0" @click="activeView==='trash'?undefined:selectTaskUnlessSwiped(node.task)" @keydown.enter="activeView==='trash'?undefined:selectTaskUnlessSwiped(node.task)" @keydown.space.prevent="activeView==='trash'?undefined:selectTaskUnlessSwiped(node.task)"><strong :title="node.task.title">{{node.task.title}}</strong><span v-if="node.subtasks.length" class="meta"><span class="meta-item"><ListChecks/>{{node.subtasks.filter(t=>t.completed).length}}/{{node.subtasks.length}}</span></span><span v-if="node.task.priority" class="priority" :class="`p${node.task.priority}`">{{['','低','中','高'][node.task.priority]}}</span></div>
-            <span v-if="node.task.due_at" class="task-tail"><TaskDueDisplay :due-at="node.task.due_at" :due-has-time="node.task.due_has_time" :completed="node.task.completed" :now-ms="taskDueNowMs" /></span><span v-if="activeView==='trash'" class="task-actions"><button class="restore" @click.stop="restoreTask(node.task)"><ArchiveRestore/>恢复</button><button class="icon danger ghost" aria-label="永久删除" @click.stop="purgeTask(node.task)"><X/></button></span><span v-else class="task-actions"><button class="icon ghost task-detail-trigger" aria-label="打开任务详情" @click.stop="selectTask(node.task)"><Ellipsis/></button></span>
+            <span v-if="node.task.due_at" class="task-tail"><TaskDueDisplay :due-at="node.task.due_at" :due-has-time="node.task.due_has_time" :completed="node.task.completed" :now-ms="taskDueNowMs" /></span><span v-if="activeView==='trash'" class="task-actions"><button class="restore" @click.stop="restoreTask(node.task)"><ArchiveRestore/>恢复</button><button class="icon danger ghost" aria-label="永久删除" @click.stop="purgeTask(node.task)"><X/></button></span>
           </article>
         </template>
         <div v-if="activeView==='today' && !query && hiddenCompletedTaskCount > 0 && !visibleTasks.length && !loading" class="today-filtered-empty-note"><span>已隐藏已完成任务</span><button type="button" class="link" @click="showCompleted=true">显示</button></div>