feat(ap01): use levitation for mass rebuilds

To deal with mass rebuild disk space requirements, we can just levitate.

In the future, we will use levitation as a general-purpose mechanism for
partition layout migration, etc.

Signed-off-by: Ryan Lahfa <ryan@dgnum.eu>

machines/ap01/_configuration.nix

@@ -224,6 +224,36 @@ rec {
   defaultProfile.packages = with pkgs; [
     zyxel-bootconfig
     min-collect-garbage
-    mtdutils
+    iwinfo
+    ifwait
+    # Levitate enable us to mass-reinstall the system on the fly.
+    (levitate.override {
+      config = {
+        imports = [
+          "${modulesPath}/network"
+          "${modulesPath}/ssh"
+          "${modulesPath}/hardware.nix"
+          "${modulesPath}/kernel"
+          "${modulesPath}/outputs/tftpboot.nix"
+          "${modulesPath}/outputs.nix"
+        ];
+        services = {
+          # Simplest DHCPv4 we can find.
+          dhcpv4 = svc.network.dhcp.client.build {
+            interface = config.hardware.networkInterfaces.lan;
+          };
+          inherit (config.services) sshd;
+          defaultroute4 = svc.network.route.build {
+            via = "$(output ${services.dhcpv4} router)";
+            target = "default";
+            dependencies = [ config.services.dhcpv4 ];
+          };
+        };
+
+        defaultProfile.packages = [ mtdutils ];
+        # Only keep root, which should inherit from DGN access control's root permissions.
+        users.root = config.users.root;
+      };
+    })
   ];
 }