feat: add the possibility to add registry mirrors

roles/base/defaults/main.yml

@@ -7,3 +7,8 @@ docker_compose_base_dir: /etc/docker/compose
 
 # Global docker volume directory configuration
 docker_volume_base_dir: /srv/data
+
+# Docker registry mirror configuration
+# Set to empty list to disable registry mirror
+# Example: docker_registry_mirrors: ["https://mirror.example.com"]
+docker_registry_mirrors: []