Security hardening (#426)

- Switch gid and supplementary groups to user's when reading user's
  config
- Only show users between UID_MIN and UID_MAX in /etc/login.defs
- Open accountsservice icons with O_NOFOLLOW to explicitly disallow
  symlinks

daemon/Cargo.toml

@@ -23,6 +23,7 @@ serde.workspace = true
 zbus.workspace = true
 cosmic-randr-shell.workspace = true
 kdl.workspace = true
+whitespace-conf = "1"
 
 #TODO: reduce features
 tokio = { workspace = true, features = ["full"] }