Getting notified if a chapter is unavailable during Library updates

[Goku003]

Why/User Benefit/User Problem

With this feature, user will be notified if any of the manga in the library has unavailable chapters(This happens for manga which has official version or scanlating group pulling all the chapters from dex) and if needed it can be migrated to another source or merging it with mangalife(missing chapters wont be present if latest chapters are pulled)

What/Requirements

After library updates, notify the user with list of chapters been removed from the manga.