[ENHANCEMENT] cleanup: remove file from greenpass when source is deleted

[amarradi]

Is it possible to carry out a kind of "cleaning"? I empty my download folder and delete old files that I no longer need.

However, they can still be accessed in greenpass for the time being. The function should be able to be started manually and check whether the original source is still available, if not then remove from greenpass with or without queries you can decide for yourself. That would be a great feature for me to work more clearly again