Remove nix from backups and migrate k3s to agent

modules/nixos/my_btrbk/default.nix

@@ -41,9 +41,6 @@ in
           "/home" = {
             snapshot_name = "home";
           };
-          "/nix" = {
-            snapshot_name = "nix";
-          };
         };
         snapshot_dir = "/.btrbk_snapshots";
         target = "send-receive ssh://10.0.0.5/zpool-backup/backups/${config.networking.hostName}";

systems/x86_64-linux/penguin/default.nix

@@ -31,18 +31,15 @@ in
       sshKeyFile = config.age.secrets.btrbk-keyfile.path;
     };
 
-
     my_k3s = {
       enable = true;
+      role = "agent";
       tokenFile = config.age.secrets.k3s.path;
+      clusterInit = false;
       serverAddr = "https://10.222.0.13:6443";
       extraFlags = [
-        "--disable=servicelb"
-        "--disable=traefik"
         "--node-ip 10.222.0.249"
         "--flannel-iface ztxh6lvd6t"
-        "--flannel-backend=host-gw"
-        "--tls-san 10.222.0.249"
       ];
       nvidia = true;
     };
@@ -73,7 +70,7 @@ in
 
     networking = {
       networkmanager.enable = true;
-      nftables.enable = true;
+      nftables.enable = false;
       firewall = {
         enable = true;
         allowedTCPPorts = [