misc: refactor imports, prefer adding helpers to args rather than importing it

plugins/filetrees/chadtree.nix

@@ -1,12 +1,12 @@
 {
-  pkgs,
-  config,
   lib,
+  helpers,
+  config,
+  pkgs,
   ...
 }:
 with lib; let
   cfg = config.plugins.chadtree;
-  helpers = import ../helpers.nix {inherit lib;};
   mkListStr = helpers.defaultNullOpts.mkNullable (types.listOf types.str);
 in {
   options.plugins.chadtree =

plugins/filetrees/neo-tree.nix

@@ -1,13 +1,12 @@
 {
-  pkgs,
-  config,
   lib,
+  helpers,
+  config,
+  pkgs,
   ...
 }:
 with lib; let
   cfg = config.plugins.neo-tree;
-  helpers = import ../helpers.nix {inherit lib;};
-
   basePluginPath = ["plugins" "neo-tree"];
 in {
   imports = [

plugins/filetrees/nvim-tree.nix

@@ -1,12 +1,12 @@
 {
+  lib,
+  helpers,
   pkgs,
   config,
-  lib,
   ...
-} @ args:
+}:
 with lib; let
   cfg = config.plugins.nvim-tree;
-  helpers = import ../helpers.nix {inherit lib;};
   inherit (helpers) ifNonNull';
 
   openWinConfigOption =