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

roles/docker/tasks/main.yml

@@ -0,0 +1,62 @@
+---
+- name: Install prerequisites for Docker
+  apt:
+    name:
+      - curl
+      - gnupg
+      - ca-certificates
+      - lsb-release
+    state: present
+    update_cache: yes
+  tags: docker
+
+- name: Install Docker using official script
+  shell: |
+    curl -fsSL https://get.docker.com -o /tmp/get-docker.sh
+    sh /tmp/get-docker.sh
+    rm /tmp/get-docker.sh
+  args:
+    creates: /usr/bin/docker
+  tags: docker
+
+- name: Install Docker Compose
+  get_url:
+    url: "https://github.com/docker/compose/releases/download/{{ docker_compose_version }}/docker-compose-linux-x86_64"
+    dest: "{{ docker_compose_install_path }}"
+    mode: '0755'
+    timeout: 30
+  tags: docker
+
+- name: Start and enable Docker service
+  systemd:
+    name: docker
+    state: started
+    enabled: yes
+    daemon_reload: yes
+  tags: docker
+
+- name: Add admin user to docker group
+  user:
+    name: admin
+    groups: docker
+    append: yes
+  tags: docker
+
+- name: Verify Docker installation
+  command: docker --version
+  register: docker_version
+  changed_when: false
+  tags: docker
+
+- name: Verify Docker Compose installation
+  command: docker-compose --version
+  register: docker_compose_version
+  changed_when: false
+  tags: docker
+
+- name: Show installation results
+  debug:
+    msg:
+      - "Docker: {{ docker_version.stdout }}"
+      - "Docker Compose: {{ docker_compose_version.stdout }}"
+  tags: docker