feat: 使用banana模型生成分镜图片，修复数据库列类型问题

- 修改RealAIService.submitTextToImageTask使用nano-banana/nano-banana-hd模型
- 支持根据hdMode参数选择模型（标准/高清）
- 修复数据库列类型：将result_url等字段改为TEXT类型以支持Base64图片
- 添加数据库修复SQL脚本（fix_database_columns.sql, update_database_schema.sql）
- 改进StoryboardVideoService的错误处理和空值检查
- 添加GlobalExceptionHandler全局异常处理
- 优化图片URL提取逻辑，支持url和b64_json两种格式
- 改进响应格式验证，确保data字段不为空

demo/frontend/src/views/MyWorks.vue

@@ -130,7 +130,25 @@
       <el-col v-for="item in filteredItems" :key="item.id" :xs="24" :sm="12" :md="8" :lg="6">
         <el-card class="work-card" :class="{ selected: selectedIds.has(item.id) }" shadow="hover">
           <div class="thumb" @click="multiSelect ? toggleSelect(item.id) : openDetail(item)">
-            <img :src="item.cover" :alt="item.title" />
+            <!-- 如果是视频类型且有视频URL，使用video元素显示首帧 -->
+            <video 
+              v-if="item.type === 'video' && item.resultUrl" 
+              :src="item.resultUrl" 
+              class="work-thumbnail-video"
+              muted
+              preload="metadata"
+              @loadedmetadata="onVideoLoaded"
+            ></video>
+            <!-- 如果有封面图（thumbnailUrl），使用图片 -->
+            <img 
+              v-else-if="item.cover && item.cover !== item.resultUrl" 
+              :src="item.cover" 
+              :alt="item.title" 
+            />
+            <!-- 否则使用默认占位符 -->
+            <div v-else class="work-placeholder">
+              <el-icon><VideoPlay /></el-icon>
+            </div>
             
             <div class="checker" v-if="multiSelect">
               <el-checkbox :model-value="selectedIds.has(item.id)" @change="() => toggleSelect(item.id)" />
@@ -191,7 +209,7 @@
             <video 
               v-if="selectedItem.type === 'video'"
               class="detail-video"
-              :src="selectedItem.cover"
+              :src="selectedItem.resultUrl || selectedItem.cover"
               :poster="selectedItem.cover"
               controls
             >
@@ -314,7 +332,7 @@
 import { ref, onMounted, computed } from 'vue'
 import { useRouter } from 'vue-router'
 import { ElMessage, ElMessageBox } from 'element-plus'
-import { Star, User, Compass, Document, VideoPlay, Picture, Film, Bell, Setting, Search } from '@element-plus/icons-vue'
+import { Star, User, Compass, Document, VideoPlay, Picture, Film, Bell, Setting, Search, MoreFilled } from '@element-plus/icons-vue'
 import { getMyWorks } from '@/api/userWorks'
 
 const router = useRouter()
@@ -341,6 +359,28 @@ const loading = ref(false)
 const hasMore = ref(true)
 const items = ref([])
 
+// 将后端返回的UserWork数据转换为前端需要的格式
+const transformWorkData = (work) => {
+  return {
+    id: work.id?.toString() || work.taskId || '',
+    title: work.title || work.prompt || '未命名作品',
+    cover: work.thumbnailUrl || work.resultUrl || '/images/backgrounds/welcome.jpg',
+    resultUrl: work.resultUrl || '',
+    type: work.workType === 'TEXT_TO_VIDEO' || work.workType === 'IMAGE_TO_VIDEO' ? 'video' : 'image',
+    category: work.workType === 'TEXT_TO_VIDEO' ? '文生视频' : work.workType === 'IMAGE_TO_VIDEO' ? '图生视频' : '未知',
+    sizeText: work.fileSize || '未知大小',
+    createTime: work.createdAt ? new Date(work.createdAt).toLocaleString('zh-CN') : '',
+    date: work.createdAt ? new Date(work.createdAt).toLocaleDateString('zh-CN') : '',
+    description: work.description || work.prompt || '',
+    prompt: work.prompt || '',
+    duration: work.duration || '',
+    aspectRatio: work.aspectRatio || '',
+    quality: work.quality || '',
+    status: work.status || 'COMPLETED',
+    overlayText: work.prompt || ''
+  }
+}
+
 const loadList = async () => {
   loading.value = true
   try {
@@ -352,8 +392,11 @@ const loadList = async () => {
     if (response.data.success) {
       const data = response.data.data || []
       
+      // 转换数据格式
+      const transformedData = data.map(transformWorkData)
+      
       if (page.value === 1) items.value = []
-      items.value = items.value.concat(data)
+      items.value = items.value.concat(transformedData)
       hasMore.value = data.length === pageSize.value
     } else {
       throw new Error(response.data.message || '获取作品列表失败')
@@ -545,6 +588,17 @@ const resetFilters = () => {
   ElMessage.success('筛选器已重置')
 }
 
+// 视频加载元数据后，跳转到第一帧（但不播放）
+const onVideoLoaded = (event) => {
+  const video = event.target
+  if (video && video.duration) {
+    // 跳转到第一帧（0秒）
+    video.currentTime = 0.1
+    // 确保视频不播放
+    video.pause()
+  }
+}
+
 onMounted(() => {
   loadList()
 })
@@ -799,6 +853,28 @@ onMounted(() => {
 .work-card { margin-bottom: 14px; }
 .thumb { position: relative; width: 100%; padding-top: 56.25%; overflow: hidden; border-radius: 6px; cursor: pointer; }
 .thumb img { position: absolute; top: 0; left: 0; width: 100%; height: 100%; object-fit: cover; }
+.work-thumbnail-video {
+  position: absolute;
+  top: 0;
+  left: 0;
+  width: 100%;
+  height: 100%;
+  object-fit: cover;
+  pointer-events: none;
+}
+.work-placeholder {
+  position: absolute;
+  top: 0;
+  left: 0;
+  width: 100%;
+  height: 100%;
+  background: rgba(0, 0, 0, 0.3);
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  color: #999;
+  font-size: 24px;
+}
 .checker { position: absolute; left: 6px; top: 6px; }
 .actions { position: absolute; right: 6px; top: 6px; display: flex; gap: 4px; opacity: 0; transition: opacity .2s ease; }
 .thumb:hover .actions { opacity: 1; }