Enable IPv6 support for K8s

Enable DNS over IPv6 and TCP to comply with isnic
Provision k3s CA
Make Atlas a k8s agent instead of server

machines/atlas.nix

@@ -10,6 +10,7 @@
 
       k3s = {
         enable = true;
+        role = "agent";
         serverAddr = "https://jefke.dmz:6443";
       };
     };

machines/jefke.nix

@@ -8,7 +8,10 @@
         dataPartition = "/dev/nvme0n1p1";
       };
 
-      k3s.enable = true;
+      k3s = {
+        enable = true;
+        clusterInit = true;
+      };
     };
   };
 }