failed to invalidate local cache when work on memoryfs

https://github.com/HeyPuter/puter/commit/ebb0162d795b571a844ff67e44874689f233f6d0#diff-85adde2cd8d785d505ef36ffc59056a69bb15fdf6a963d48fff7186ab6353a90 introduced a new mechanism that relies solely on filesystem events for cache invalidation. This doesn't work on memoryfs since it doesn't send fs events. (puterfs does)