chore: organise modules

Organise modules in a significantly better way with categories.

modules/desktop/login/autologin.nix

@@ -0,0 +1,17 @@
+{ config, lib, pkgs, ... }:
+
+{
+  # Enable display manager w/autologin
+  services.greetd = {
+    enable = true;
+    settings = {
+      initial_session = {
+        command = if (config.programs.niri.enable == true) then "${pkgs.niri}/bin/niri-session" else if (config.programs.hyprland.enable == true) then "${pkgs.hyprland}/bin/Hyprland" else "${pkgs.zsh}/bin/zsh";
+        user = "nico";
+      };
+      default_session = {
+        command = "${pkgs.greetd.tuigreet}/bin/tuigreet --asterisks --time --greeting 'nyaaa~~'";
+      };
+    };
+  };
+}