modules: move tui, gui, cli to programs

modules/programs/editors/nvf/plugins/settings/treesitter.nix

@@ -0,0 +1,20 @@
+{
+  config,
+  pkgs,
+  ...
+}: let
+  inherit (config.modules.other.system) username;
+in {
+  programs.neovim-flake.settings.vim = {
+    treesitter = {
+      fold = true;
+      context.enable = false; # FIXME: currently broken, I do not know why.
+
+      # extra grammars that will be installed by Nix
+      grammars = with pkgs.vimPlugins.nvim-treesitter.builtGrammars; [
+        regex # for regexplainer
+        kdl # zellij configurations are in KDL, I want syntax highlighting
+      ];
+    };
+  };
+}