fix: remake admin items

backend/handlers/item_handlers.go

@@ -74,7 +74,6 @@ func UpdateItem(c *gin.Context) {
 		City:     input.City,
 		Price:    input.Price,
 		Category: input.Category,
-		Stock: input.Stock,
 	})
 
 	c.JSON(http.StatusOK, item)

frontend/src/components/AdminItems.jsx

@@ -116,6 +116,7 @@ function ItemFormModal({ item, onClose, onSaved }) {
             placeholder="Остаток"
             value={form.stock}
             onChange={handleChange("stock")}
+            disabled
           />
           <input
             className="bg-white/10 rounded px-3 py-2"