Cleanup route handling (#542)

* mikrotik: allow to set DNS, wip: handle routes in wg-controller

* replace old route handling for local controller

* cleanup route handling for local backend

* implement route handling for mikrotik controller

internal/lowlevel/mikrotik.go

@@ -267,6 +267,7 @@ func parseHttpResponse[T any](resp *http.Response, err error) MikrotikApiRespons
 	}
 
 	defer func(Body io.ReadCloser) {
+		_, _ = io.Copy(io.Discard, Body) // ensure to empty the body
 		err := Body.Close()
 		if err != nil {
 			slog.Error("failed to close response body", "error", err)