Add nvim-lazy submodule and add plugin configuration.

pkgsets/nvim.nix

@@ -0,0 +1,40 @@
+{
+  lib,
+  config,
+  fn,
+  nvim-lazy,
+  ...
+}:
+
+with lib;
+{
+  imports =
+    [
+      nvim-lazy.nixosModules.nvim-lazy
+    ]
+    ++ (fn.lst {
+      path = (toString ./nvim);
+      fullPath = true;
+    });
+
+  programs.nvim-lazy = mkIf (elem "nvim" config.machine.pkgs) {
+    enable = true;
+    luaRcContent = # lua
+      ''
+        vim.g.mapleader = " "
+        vim.opt.tabstop = 2
+        vim.opt.shiftwidth = 2
+        vim.opt.expandtab = true
+        vim.opt.ignorecase = true
+        vim.opt.smartcase = true
+        -- TODO: fix option name
+        -- vim.opt.nformats = alpha
+        vim.bo.softtabstop = 2
+
+        vim.wo.number = true
+        vim.wo.relativenumber = true
+
+        vim.opt.scrolloff = 10
+      '';
+  };
+}