feat: add blackbox monitoring and app3 deployment

- Add blackbox exporter role and playbooks
- Add cadvisor, docker, httpbin roles
- Add app3 deployment playbooks
- Configure blackbox monitoring

playbooks/configure-blackbox-monitoring.yml

@@ -0,0 +1,43 @@
+---
+- name: Configure Prometheus for Blackbox monitoring
+  hosts: 192.168.0.105
+  become: yes
+
+  vars:
+    blackbox_targets: "{{ hostvars['192.168.0.112']['blackbox_targets'] }}"
+
+  tasks:
+    - name: Add blackbox exporter to Prometheus
+      blockinfile:
+        path: /etc/prometheus/prometheus.yml
+        insertafter: '  # cAdvisor container metrics'
+        block: |
+          # Blackbox Exporter probes
+          - job_name: 'blackbox'
+            metrics_path: /probe
+            params:
+              module: [http_2xx]
+            static_configs:
+              - targets:
+                {% for target in blackbox_targets %}
+                - {{ target.url }}
+                {% endfor %}
+            relabel_configs:
+              - source_labels: [__address__]
+                target_label: __param_target
+              - source_labels: [__param_target]
+                target_label: instance
+              - target_label: __address__
+                replacement: 192.168.0.112:8083  # blackbox-exporter
+        marker: "# {mark} ANSIBLE MANAGED BLOCK - blackbox"
+
+    - name: Check Prometheus configuration
+      command: promtool check config /etc/prometheus/prometheus.yml
+      register: promtool_check
+      failed_when: promtool_check.rc != 0
+
+    - name: Reload Prometheus
+      systemd:
+        name: prometheus
+        state: reloaded
+      when: promtool_check.rc == 0