feat(design): 添加360视频和3D模型生成功能支持

- 在Design模型中新增video_url字段用于存储360度展示视频URL
- 在DesignImage模型中新增model_3d_url字段用于存储3D模型URL
- 设计路由新增生成视频接口，调用火山引擎即梦3.0 Pro API生成展示视频
- 设计路由新增生成3D模型接口，调用腾讯混元3D服务生成.glb格式3D模型
- 新增本地文件删除工具，支持强制重新生成时清理旧文件
- 设计响应Schema中添加video_url和model_3d_url字段支持前后端数据传递
- 前端设计详情页新增360度旋转3D模型展示区，支持生成、重新生成和下载3D模型
- 实现录制3D模型展示视频功能，支持捕获model-viewer旋转画面逐帧合成WebM文件下载
- 引入@google/model-viewer库作为3D模型Web组件展示支持
- 管理后台新增即梦视频生成和腾讯混元3D模型生成配置界面，方便服务密钥管理
- 前端API增加生成视频和生成3D模型接口请求方法，超时设置为10分钟以支持长时间处理
- 优化UI交互提示，新增生成中状态显示和错误提示，提升用户体验和操作反馈

backend/app/routers/designs.py

@@ -1,17 +1,40 @@
 """
 设计相关路由
-提供设计生成、查询、删除、下载接口
+提供设计生成、查询、删除、下载、视频生成、3D模型生成接口
 """
 import os
+import logging
 from fastapi import APIRouter, Depends, HTTPException, status, Query
 from fastapi.responses import FileResponse, RedirectResponse
 from sqlalchemy.orm import Session
 
 from ..database import get_db
-from ..models import User, Design
+from ..models import User, Design, DesignImage
 from ..schemas import DesignCreate, DesignResponse, DesignListResponse, DesignImageResponse
 from ..utils.deps import get_current_user
 from ..services import design_service
+from ..services import ai_video_generator
+from ..services import ai_3d_generator
+
+logger = logging.getLogger(__name__)
+
+# uploads 基础目录
+UPLOADS_BASE = os.path.join(os.path.dirname(os.path.dirname(os.path.dirname(__file__))), "uploads")
+
+
+def _delete_local_file(url_path: str):
+    """删除本地存储的文件（如 /uploads/videos/xxx.mp4）"""
+    if not url_path or not url_path.startswith("/uploads/"):
+        return
+    rel_path = url_path.lstrip("/uploads/")
+    full_path = os.path.join(UPLOADS_BASE, rel_path)
+    if os.path.exists(full_path):
+        try:
+            os.remove(full_path)
+            logger.info(f"已删除旧文件: {full_path}")
+        except Exception as e:
+            logger.warning(f"删除旧文件失败: {full_path}, {e}")
+
 
 router = APIRouter(prefix="/api/designs", tags=["设计"])
 
@@ -29,6 +52,7 @@ def design_to_response(design: Design) -> DesignResponse:
                 model_used=img.model_used,
                 prompt_used=img.prompt_used,
                 sort_order=img.sort_order,
+                model_3d_url=img.model_3d_url,
             )
             for img in design.images
         ]
@@ -66,6 +90,7 @@ def design_to_response(design: Design) -> DesignResponse:
         surface_finish=design.surface_finish,
         usage_scene=design.usage_scene,
         image_url=design.image_url,
+        video_url=design.video_url,
         images=images,
         status=design.status,
         created_at=design.created_at,
@@ -219,3 +244,115 @@ def download_design(
         filename=f"design_{design_id}.png",
         media_type="image/png"
     )
+
+
+@router.post("/{design_id}/generate-video", response_model=DesignResponse)
+async def generate_video(
+    design_id: int,
+    force: bool = Query(False, description="强制重新生成"),
+    db: Session = Depends(get_db),
+    current_user: User = Depends(get_current_user)
+):
+    """
+    为设计生成 360 度旋转展示视频
+    取设计的多视角图片，通过火山引擎即梦 3.0 Pro 生成视频
+    """
+    design = design_service.get_design_by_id(db=db, design_id=design_id, user_id=current_user.id)
+    if not design:
+        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="设计不存在")
+
+    # 已有视频且不强制重生时直接返回
+    if design.video_url and not force:
+        return design_to_response(design)
+
+    # 强制重生时删除旧视频文件
+    if force and design.video_url:
+        _delete_local_file(design.video_url)
+        design.video_url = None
+
+    # 收集多视角图片 URL
+    image_urls = []
+    if design.images:
+        for img in sorted(design.images, key=lambda x: x.sort_order):
+            if img.image_url:
+                image_urls.append(img.image_url)
+    if not image_urls and design.image_url:
+        image_urls.append(design.image_url)
+
+    if not image_urls:
+        raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail="设计没有图片，无法生成视频")
+
+    logger.info(f"设计 {design_id} 生成视频，共收集到 {len(image_urls)} 张图片")
+
+    try:
+        video_url = await ai_video_generator.generate_video(image_urls)
+        design.video_url = video_url
+        db.commit()
+        db.refresh(design)
+        return design_to_response(design)
+    except Exception as e:
+        logger.error(f"视频生成失败: {e}")
+        raise HTTPException(
+            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
+            detail=f"视频生成失败: {str(e)}"
+        )
+
+
+@router.post("/{design_id}/generate-3d", response_model=DesignResponse)
+async def generate_3d_model(
+    design_id: int,
+    force: bool = Query(False, description="强制重新生成"),
+    db: Session = Depends(get_db),
+    current_user: User = Depends(get_current_user)
+):
+    """
+    为设计生成 3D 模型
+    收集所有多视角图片，取效果图（45度视角）生成 .glb 格式 3D 模型
+    """
+    design = design_service.get_design_by_id(db=db, design_id=design_id, user_id=current_user.id)
+    if not design:
+        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="设计不存在")
+
+    # 检查是否已有 3D 模型（第一张图片）
+    if design.images and not force:
+        first_img = sorted(design.images, key=lambda x: x.sort_order)[0]
+        if first_img.model_3d_url:
+            return design_to_response(design)
+
+    # 强制重生时删除旧文件
+    if force and design.images:
+        first_img = sorted(design.images, key=lambda x: x.sort_order)[0]
+        if first_img.model_3d_url:
+            _delete_local_file(first_img.model_3d_url)
+            first_img.model_3d_url = None
+
+    # 收集所有多视角图片 URL 和视角名称
+    image_urls = []
+    view_names = []
+    if design.images:
+        for img in sorted(design.images, key=lambda x: x.sort_order):
+            if img.image_url:
+                image_urls.append(img.image_url)
+                view_names.append(img.view_name or "效果图")
+    if not image_urls and design.image_url:
+        image_urls.append(design.image_url)
+        view_names.append("效果图")
+
+    if not image_urls:
+        raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail="设计没有图片，无法生成3D模型")
+
+    try:
+        model_url = await ai_3d_generator.generate_3d_model(image_urls, view_names)
+        # 将 3D 模型 URL 保存到第一张图片
+        if design.images:
+            first_img = sorted(design.images, key=lambda x: x.sort_order)[0]
+            first_img.model_3d_url = model_url
+        db.commit()
+        db.refresh(design)
+        return design_to_response(design)
+    except Exception as e:
+        logger.error(f"3D 模型生成失败: {e}")
+        raise HTTPException(
+            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
+            detail=f"3D 模型生成失败: {str(e)}"
+        )