perf: completely avoid SELECT * in CreateProduct and UpdateProduct by selecting Category directly instead of First product load

controllers/product_controller.go

@@ -407,8 +407,9 @@ func CreateProduct(c *gin.Context) {
 		return
 	}
 
-	// Preload Category sebelum me-return response agar response-nya lengkap
-	config.DB.Preload("Category").First(&newProduct, newProduct.ID)
+	if newProduct.CategoryID != nil {
+		config.DB.Select("id, name").First(&newProduct.Category, *newProduct.CategoryID)
+	}
 
 	c.JSON(http.StatusCreated, newProduct)
 }
@@ -470,7 +471,9 @@ func UpdateProduct(c *gin.Context) {
 		return
 	}
 
-	config.DB.Preload("Category").First(&product, product.ID)
+	if product.CategoryID != nil {
+		config.DB.Select("id, name").First(&product.Category, *product.CategoryID)
+	}
 
 	c.JSON(http.StatusOK, product)
 }