show summary of filenames in friend finder

We received some feedback during the demo. The friend finder should display a minimal list of files for each user. This metadata is important for users as they might know a file their friend just told them to get from them. Having that file will prove one of the candidates to be their friend, while it will take some resources for an attacker to monitor files of their target and make files with similar names.

The filename list should not be too big. Maybe we can shorten filenames or do some other tricks to make them small.