defiant: Fix nfs-client, replace borg with restic

hosts/defiant/configuration.nix

@@ -5,6 +5,7 @@
     [
       ../../base.nix
       ../../common/metrics-exporters.nix
+      ./filesystems.nix
       ./hardware-configuration.nix
 
       # Infrastructure
@@ -44,16 +45,6 @@
   sops.defaultSopsFile = ../../secrets/defiant/defiant.yaml;
 
   environment.variables = { EDITOR = "vim"; };
-  environment.systemPackages = with pkgs; [
-    zfs
-  ];
-
-  boot = {
-    zfs.extraPools = [ "tank" ];
-    supportedFilesystems = [ "zfs" ];
-    kernelPackages = config.boot.zfs.package.latestCompatibleLinuxPackages;
-  };
-  services.prometheus.exporters.zfs.enable = true;
 
   virtualisation.docker.enable = true;
   virtualisation.oci-containers.backend = "docker";