Update openclaw role for Margaret Docker deployment

- Updated defaults: custom image, container name, config paths
- Updated compose template: proper CMD, HOME env, user mapping
- Updated tasks: image existence check, warning if not found
- Added handlers: restart on compose changes
- Image must be pre-built on Bart (16GB RAM) and transferred

roles/openclaw/handlers/main.yml

@@ -0,0 +1,6 @@
+---
+- name: Restart Margaret
+  community.docker.docker_compose_v2:
+    project_src: "{{ openclaw_compose_dir }}"
+    state: restarted
+  tags: [openclaw, margaret]