fix: Formatting

Working:
  - The daemon
  - Mutable config — well, kinda. I'm not yet sure how it will interact with
    `emacsWithPackagesFromUsePackage`.
  - Packages via Nixpkgs

outputs/homeConfigurations.nix

@@ -13,6 +13,7 @@ let users = builtins.readDir ../users;
         # Directory name should always match username.
         ({ ... }: { home.username = username; })
 
+        # TODO: Move to default module.
         ({ lib, ... }: {
           nix = {
             settings.experimental-features =