titan-jh: enable node exporter

hosts/roles/titan_jh/tasks/main.yaml

@@ -1,5 +1,18 @@
 # hosts/roles/titan_jh/tasks/main.yaml
 ---
+- name: Install node exporter
+  ansible.builtin.package:
+    name: prometheus-node-exporter
+    state: present
+  tags: ['jumphost', 'monitoring']
+
+- name: Enable node exporter
+  ansible.builtin.service:
+    name: prometheus-node-exporter
+    enabled: true
+    state: started
+  tags: ['jumphost', 'monitoring']
+
 - name: Placeholder for jumphost hardening
   ansible.builtin.debug:
     msg: "Harden SSH, manage bastion tooling, and configure audit logging here."