adding beszel agents

hosts/h003/monitoring_agent.nix

@@ -0,0 +1,32 @@
+{
+  inputs,
+  config,
+  hostConfig,
+  ...
+}:
+let
+  declaration = "services/monitoring/beszel-agent.nix";
+  nixpkgs = inputs.beszel-nixpkgs;
+  pkgs = import nixpkgs {
+    system = "x86_64-linux";
+    config.allowUnfree = true;
+  };
+in
+{
+  disabledModules = [ declaration ];
+  imports = [ "${nixpkgs}/nixos/modules/${declaration}" ];
+  config = {
+    services.beszel.agent = {
+      package = pkgs.beszel;
+      enable = true;
+      environment = {
+        SYSTEM_NAME = config.networking.hostName;
+        LISTEN = "${hostConfig.overlayIp}:45876";
+        HUB_URL = "http://100.64.0.13:8090";
+        # TODO this is only safe since I am running it in the overlay network only, rotate all keys if we change that.
+        TOKEN = "20208198-87c2-4bd1-ab09-b97c3b9c6a6e";
+        KEY = "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIDcAr8fbW4XyfL/tCMeMtD+Ou/FFywCNfsHdyvYs3qXf";
+      };
+    };
+  };
+}