fix: 添加分类名称唯一约束，防止重复名称

backend/internal/api/handlers/article.go

@@ -5,7 +5,6 @@ import (
 	"net/http"
 	"strconv"
 
-	"sale/internal/crawler"
 	"sale/internal/models"
 	"sale/internal/schemas"
 	"sale/internal/utils"
@@ -164,15 +163,3 @@ func (h *ArticleHandler) TogglePin(c *gin.Context) {
 	utils.DB.First(&article, id)
 	c.JSON(http.StatusOK, gin.H{"data": article})
 }
-
-// CrawlRibenyan 采集 ribenyan.com 文章
-func (h *ArticleHandler) CrawlRibenyan(c *gin.Context) {
-	crawler := crawler.NewRibenyanCrawler(utils.DB)
-	
-	if err := crawler.CrawlArticles(); err != nil {
-		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
-		return
-	}
-	
-	c.JSON(http.StatusOK, gin.H{"message": "Crawl completed successfully"})
-}

backend/internal/api/handlers/product.go

@@ -34,6 +34,12 @@ func (h *CategoryHandler) Create(c *gin.Context) {
 		return
 	}
 
+	var existing models.Category
+	if err := utils.DB.Where("name = ?", req.Name).First(&existing).Error; err == nil {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "分类名称已存在"})
+		return
+	}
+
 	category := models.Category{
 		Name:        req.Name,
 		Description: req.Description,
@@ -69,6 +75,14 @@ func (h *CategoryHandler) Update(c *gin.Context) {
 		return
 	}
 
+	if req.Name != nil && *req.Name != category.Name {
+		var existing models.Category
+		if err := utils.DB.Where("name = ? AND id != ?", *req.Name, id).First(&existing).Error; err == nil {
+			c.JSON(http.StatusBadRequest, gin.H{"error": "分类名称已存在"})
+			return
+		}
+	}
+
 	updates := make(map[string]interface{})
 	if req.Name != nil {
 		updates["name"] = *req.Name