feat(community): 友圈动态支持上传短视频，可与图片同发

- 新增 /api/upload/video 独立上传接口：仅 MP4/MOV、单条 30MB、独立限流、登录鉴权

- posts 表新增 video_url / video_cover，发布接口支持视频与图片同时落库

- 小程序发布器支持选择/预览/删除视频（≤60 秒），动态卡片与详情页支持播放

- 后台动态管理新增视频预览弹窗

- 新增短视频链路与上传鉴权回归测试，125 套件/818 用例全绿

admin/arco-design-pro-vite/src/views/community/post-manage/index.vue

@@ -105,8 +105,12 @@
             </template>
           </a-table-column>
 
-          <a-table-column title="配图" :width="160">
+          <a-table-column title="图片 / 视频" :width="170">
             <template #cell="{ record }">
+              <div v-if="record.videoUrl" class="post-video-cell">
+                <a-tag color="arcoblue" size="small">短视频</a-tag>
+                <a-button type="text" size="mini" @click="openVideoPreview(record)">播放</a-button>
+              </div>
               <a-image-preview-group v-if="record.images && record.images.length > 0">
                 <a-space wrap :size="4">
                   <a-image
@@ -120,7 +124,10 @@
                   />
                 </a-space>
               </a-image-preview-group>
-              <span v-else style="color: var(--color-text-4); font-size: 12px">纯文本无配图</span>
+              <span
+                v-if="!record.videoUrl && (!record.images || record.images.length === 0)"
+                style="color: var(--color-text-4); font-size: 12px"
+              >纯文本无配图</span>
             </template>
           </a-table-column>
 
@@ -214,6 +221,23 @@
       </a-table>
     </a-card>
 
+    <!-- 短视频预览 -->
+    <a-modal
+      v-model:visible="videoPreviewVisible"
+      :title="videoPreviewTitle"
+      :footer="false"
+      :width="560"
+      unmount-on-close
+    >
+      <video
+        v-if="videoPreviewUrl"
+        :src="videoPreviewUrl"
+        :poster="videoPreviewCover || undefined"
+        controls
+        style="width: 100%; max-height: 420px; background: #000; border-radius: 6px"
+      ></video>
+    </a-modal>
+
     <!-- 评论互动抽屉 (Drawer) -->
     <a-drawer
       v-model:visible="commentsDrawerVisible"
@@ -337,6 +361,19 @@
   const loadingApplies = ref(false);
   const appliesList = ref<any[]>([]);
 
+  // 短视频预览
+  const videoPreviewVisible = ref(false);
+  const videoPreviewUrl = ref('');
+  const videoPreviewCover = ref('');
+  const videoPreviewTitle = ref('动态短视频预览');
+
+  const openVideoPreview = (record: any) => {
+    videoPreviewUrl.value = record.videoUrl || '';
+    videoPreviewCover.value = record.videoCover || '';
+    videoPreviewTitle.value = `动态短视频 - ${record.author || ''}`;
+    videoPreviewVisible.value = true;
+  };
+
   const fetchData = async () => {
     loading.value = true;
     try {