[Feature] Broken link checker

[floviolleau]

Feature description

Hi,

Thanks for this amazing projet. I use it a lot and made my one hoster plugins for my own usage.

It would be very nice if a broken link checker could be implemented like we do have it jdownloader. Sometimes, ddl failed or take a lot of time and if we can have a feedback somewhere to see if the link is broken during the add of links. We could add as well a button in a package to run this task and check all links of a package and display a green tick ✅ or a red cross ❌

Thanks a lot Kind regards