Add feature where started videos appear at the top

[arnaldop]

This could be a toggle that could be combined with other sorts.

For example, if I sort it by video length but enable "Started Videos at the Top", I would see first the list of started videos, sorted by video length, and then I would see the videos I have not started, also sorted by video length.

[NabokD]

Thank you for sharing! You're the first who asked about it, it looks a little complicated, but we'll see