chore: move out of useless nixos directory

nixvim/config/default.nix

@@ -0,0 +1,29 @@
+{
+  # Import all your configuration modules here
+  imports = [
+    # base config
+    ./options.nix
+    ./clipboard.nix
+
+    # appearence
+    ./bufferline.nix
+    ./lualine.nix
+    ./which-key.nix
+    ./toggleterm.nix
+
+    # file and search utilities
+    ./telescope.nix
+    ./oil.nix
+
+    # language support & lsp
+    ./lsp.nix
+    ./treesitter.nix
+    ./nix.nix
+
+    # debugging
+    ./dap.nix
+
+    # autocompletion
+    ./cmp.nix
+  ];
+}