Fix pagination: all pages default to 10 per page, add total counts, fix tasks pagination position and use client-side slicing

platform/frontend/topics.html

@@ -77,7 +77,8 @@
                         </el-table-column>
                     </el-table>
                     <div v-if="!loadingTable && paginatedTopics.length === 0" class="empty-state" style="margin-top:20px;"><el-icon style="font-size:48px;color:#c0c4cc;"><IconTopic /></el-icon><div class="empty-text">暂无选题数据</div></div>
-                    <div v-if="filteredTopics.length > pageSize" style="display:flex;justify-content:center;margin:12px 0;">
+                    <div v-if="filteredTopics.length > pageSize" style="display:flex;justify-content:center;align-items:center;margin:12px 0;gap:16px;">
+                        <span style="font-size:13px;color:#909399;">共 {{ filteredTopics.length }} 条</span>
                         <el-pagination background layout="prev, pager, next" :total="filteredTopics.length" :page-size="pageSize" :current-page="currentPage" @current-change="currentPage = $event"></el-pagination>
                     </div>
                     <div class="topic-card-list" v-if="filteredTopics && filteredTopics.length > 0">
@@ -197,7 +198,7 @@ const TopicsApp = {
             publishPlatforms: { zhihu: true, wechat: true, xiaohongshu: true },
             publishing: false,
             savingContent: false,
-            currentPage: 1, pageSize: 20
+            currentPage: 1, pageSize: 10
         }
     },
     computed: {