Initial Ansible automation for hobbs.farm infrastructure

Complete IaC covering:
- 14 roles: common, docker, traefik, vaultwarden, monitoring, media, matrix,
  home_assistant, frigate, adguard, gitea, semaphore, openclaw, security, backup
- Inventory for all hosts (Peggy, Bart, Yoda, NAS, Firewalla)
- Stack playbooks: core-infrastructure, monitoring, media, communication,
  automation, smarthome, security-hardening
- Maintenance playbooks: update-containers, backup, health-check
- Production Docker Compose templates with Traefik labels
- Security hardening (sysctl, auditd, UFW, fail2ban)
- Automated backups with retention policy

roles/docker/tasks/main.yml

@@ -0,0 +1,76 @@
+---
+- name: Install Docker prerequisites
+  ansible.builtin.apt:
+    name:
+      - apt-transport-https
+      - ca-certificates
+      - curl
+      - gnupg
+      - lsb-release
+      - python3-pip
+      - python3-docker
+    state: present
+  tags: [docker, install]
+
+- name: Add Docker GPG key
+  ansible.builtin.apt_key:
+    url: https://download.docker.com/linux/ubuntu/gpg
+    state: present
+  tags: [docker, install]
+
+- name: Add Docker repository
+  ansible.builtin.apt_repository:
+    repo: "deb https://download.docker.com/linux/ubuntu {{ ansible_distribution_release }} stable"
+    state: present
+  tags: [docker, install]
+
+- name: Install Docker CE
+  ansible.builtin.apt:
+    name:
+      - docker-ce
+      - docker-ce-cli
+      - containerd.io
+      - docker-compose-plugin
+    state: present
+    update_cache: true
+  tags: [docker, install]
+
+- name: Configure Docker daemon
+  ansible.builtin.copy:
+    content: "{{ docker_daemon_options | to_nice_json }}"
+    dest: /etc/docker/daemon.json
+    owner: root
+    group: root
+    mode: "0644"
+  notify: Restart docker
+  tags: [docker, config]
+
+- name: Add users to docker group
+  ansible.builtin.user:
+    name: "{{ item }}"
+    groups: docker
+    append: true
+  loop: "{{ docker_users }}"
+  tags: [docker, users]
+
+- name: Ensure Docker is started and enabled
+  ansible.builtin.systemd:
+    name: docker
+    state: started
+    enabled: true
+  tags: [docker]
+
+- name: Create homelab Docker network
+  community.docker.docker_network:
+    name: "{{ docker_network_name }}"
+    driver: bridge
+  tags: [docker, network]
+
+- name: Ensure docker-compose base directory exists
+  ansible.builtin.file:
+    path: "{{ docker_compose_base }}"
+    state: directory
+    owner: glyptic
+    group: docker
+    mode: "0755"
+  tags: [docker]