thrall: Move most modules from flake to thrall

hosts/thrall/default.nix

@@ -2,13 +2,16 @@
 # your system.  Help is available in the configuration.nix(5) man page
 # and in the NixOS manual (accessible by running ‘nixos-help’).
 
-{ config, pkgs, ... }:
+{ inputs, config, pkgs, ... }:
 let
   authorityFromUrl = url:
     builtins.head (pkgs.lib.drop 1 (pkgs.lib.splitString "://" url));
 in {
   imports = [
     ./hardware-configuration.nix
+    inputs.snm.nixosModule
+    inputs.agenix.nixosModules.age
+    ../../modules/security.nix
     ../../modules/upgrade-pg-cluster.nix
     ../../modules/nix-config.nix
     ../../modules/iohk.nix
@@ -135,15 +138,7 @@ in {
 
   # List packages installed in system profile. To search, run:
   # $ nix search wget
-  environment.systemPackages = with pkgs; [
-    wget
-    rsync
-    htop
-    tmux
-    git
-    restic # fast and secure backup
-    rclone
-  ];
+  environment.systemPackages = with pkgs; [ wget rsync htop tmux git rclone ];
 
   # Some programs need SUID wrappers, can be configured further or are
   # started in user sessions.