fix: resolve ghost syntax error in product_handler and stabilize backend

backend/internal/http/handler/product_handler.go

@@ -227,6 +227,7 @@ func (h *Handler) SearchProducts(w http.ResponseWriter, r *http.Request) {
 			expires := time.Now().AddDate(0, 0, days)
 			filter.ExpiresAfter = &expires
 		}
+	}
 	if v := r.URL.Query().Get("expires_after"); v != "" {
 		// Also support direct date if needed
 		if t, err := time.Parse("2006-01-02", v); err == nil {