Fix Docker install for Ubuntu 22.04+ and ARM64 OCI instances

- Replace deprecated apt_key/apt_repository with modern keyrings approach (signed-by)
- Use ansible_distribution_release instead of hardcoded focal
- Auto-detect arch: arm64 for aarch64 (Ampere), amd64 for x86
- Replace docker-compose (v1, EOL) with docker-compose-plugin (v2)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

playbooks/install_docker.yml

@@ -16,25 +16,35 @@
         update_cache: true
       when: ansible_os_family == "Debian"
 
-    - name: Add Docker GPG apt Key
-      apt_key:
+    - name: Create apt keyrings directory
+      ansible.builtin.file:
+        path: /etc/apt/keyrings
+        state: directory
+        mode: '0755'
+      when: ansible_os_family == "Debian"
+
+    - name: Download Docker GPG key
+      ansible.builtin.get_url:
         url: https://download.docker.com/linux/ubuntu/gpg
-        state: present
+        dest: /etc/apt/keyrings/docker.asc
+        mode: '0644'
+        force: false
       when: ansible_os_family == "Debian"
 
     - name: Add Docker Repository
-      apt_repository:
-        repo: deb https://download.docker.com/linux/ubuntu focal stable
+      ansible.builtin.apt_repository:
+        repo: "deb [arch={{ 'arm64' if ansible_architecture == 'aarch64' else 'amd64' }} signed-by=/etc/apt/keyrings/docker.asc] https://download.docker.com/linux/ubuntu {{ ansible_distribution_release }} stable"
         state: present
+        filename: docker
       when: ansible_os_family == "Debian"
 
     - name: Update apt and install Docker packages
-      apt:
+      ansible.builtin.apt:
         name:
           - docker-ce
           - docker-ce-cli
           - containerd.io
-          - docker-compose
+          - docker-compose-plugin
         state: latest
         update_cache: true
       when: ansible_os_family == "Debian"