Docs: shorten service descriptions (#394)

* Docs: shorten service descriptions

Shorten each service introduction to one or two sentences and match the root table. Correct descriptions that no longer match upstream.

* Docs: correct service descriptions after review

Drop the AFFiNE licence sentence, which misread the Community Edition licence. Restore Subsonic-compatible for Navidrome, narrow the Dockhand licence note, and drop "no public uploads" for Gokapi, which now has file requests. Fix the FossFLOW, Picard, Hemmelig, and Beszel agent wording, restore the Bazarr order, and shorten Homebox.

* Docs: shorten the Fusion description

---------

Co-authored-by: Bart <57799908+crypt0rr@users.noreply.github.com>

Author: jackspiering