add cloud filen support

[kenkendk]

Filen is part of the latest canary builds:

Release: 2.1.0.118 (Canary) 2025-05-12

2.1.0.118_canary_2025-05-12 This release is a canary release intended to be used for testing. Major changes in this version This version has a number of minor fixes and a major rewrite of the the “repair” command. The logic for the “repair” command is that it should be possible to recover loss of .dblock files, if the data is still present locally. This logic has been fixed in multiple ways and now also supports recovering data, even if no individual .dblock volumes can be fully recovered. I…