feat: 导航收藏网站 v1.0

- 左侧边栏分类导航
- 紫蓝渐变背景
- 精致卡片设计
- 网站增删改查、收藏功能
- 搜索过滤
- 后端: Flask + MySQL
- 前端: React + Vite

backend/main.py

@@ -140,15 +140,15 @@ def get_websites():
             
             # 转换日期时间并添加分类信息
             for site in websites:
-                if site.get('created_at'):
+                if site.get('created_at') and hasattr(site['created_at'], 'isoformat'):
                     site['created_at'] = site['created_at'].isoformat()
-                if site.get('updated_at'):
+                if site.get('updated_at') and hasattr(site['updated_at'], 'isoformat'):
                     site['updated_at'] = site['updated_at'].isoformat()
                 
                 cat_id = site.get('category_id')
                 if cat_id and cat_id in categories:
                     cat = categories[cat_id]
-                    if cat.get('created_at'):
+                    if cat.get('created_at') and hasattr(cat['created_at'], 'isoformat'):
                         cat['created_at'] = cat['created_at'].isoformat()
                     site['category'] = cat
                 else: