refactor: removing needless module complexity

modules/home/programs/nixvim/plugins/markdown-preview.nix

@@ -0,0 +1,33 @@
+{
+  lib,
+  config,
+  ...
+}: let
+  inherit (lib) mkEnableOption mkIf;
+  cfg = config.home.devtools.nixvim.plugins.markdown-preview;
+in {
+  options = {
+    home.devtools.nixvim.plugins.markdown-preview.enable = mkEnableOption "Enables Markdown Preview plugin for nixvim";
+  };
+
+  config = mkIf cfg.enable {
+    programs.nixvim = {
+      plugins.markdown-preview = {
+        enable = true;
+
+        settings = {
+          auto_close = false;
+          theme = "dark";
+        };
+      };
+
+      files."after/ftplugin/markdown.lua".keymaps = [
+        {
+          mode = "n";
+          key = "<leader>m";
+          action = ":MarkdownPreview<cr>";
+        }
+      ];
+    };
+  };
+}