Settings no longer shows the server's download folder (#61)

The Settings dialog ended with the server's download_dir, read-only and
the same for everyone: it is set in config.toml, so nobody can act on it
from there. The admin page still shows it.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

CHANGELOG.md

@@ -15,6 +15,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 
+- Settings no longer lists the server's download folder, which only an admin can change, on
+  the admin page.
 - On the Unread tab, a swipe back (or k) goes to the item you just read, instead of past it or
   back to the list. The items read on the way leave the Unread tab once you close the reader.