server: add linode profile init

modules/nixos/server/options.nix

@@ -0,0 +1,22 @@
+{lib, ...}: let
+  inherit (lib) mkOption;
+  inherit (lib.types) nullOr listOf enum bool;
+in {
+  options.ooknet.server = {
+    exitNode = mkOption {
+      type = bool;
+      default = false;
+      description = "Whether the server will act as a tailscale exit node or not";
+    };
+    profile = mkOption {
+      type = nullOr (enum ["linode"]);
+      default = null;
+      description = "The server profile the host will use as a base";
+    };
+    services = mkOption {
+      type = listOf (enum []);
+      default = [];
+      description = "List of services the server will host";
+    };
+  };
+}