make re-exports explicit again

Fediversity/Fediversity#269 (comment)

panel/default.nix

@@ -6,17 +6,14 @@
     config = { };
     overlays = [ (import ./nix/overlay.nix) ];
   },
-}@args:
+}:
 let
   inherit (pkgs) lib;
   manage = pkgs.writeScriptBin "manage" ''
     exec ${pkgs.lib.getExe pkgs.python3} ${toString ./src/manage.py} $@
   '';
 in
-# re-export inputs so they can be overridden granularly
-# (they can't be accessed from the outside any other way)
-args
-// {
+{
   shell = pkgs.mkShellNoCC {
     inputsFrom = [ (pkgs.callPackage ./nix/package.nix { }) ];
     packages = [
@@ -39,7 +36,12 @@ args
 
   module = import ./nix/configuration.nix;
   tests = pkgs.callPackage ./nix/tests.nix { };
+
+  # re-export inputs so they can be overridden granularly
+  # (they can't be accessed from the outside any other way)
+  inherit
+    sources
+    system
+    pkgs
+    ;
 }
-# re-export inputs so they can be overridden granularly
-# (they can't be accessed from the outside any other way)
-// args