refactor: consolidate all roles into ansible/roles/ and update ansible.cfg

- Move all roles from playbooks/roles/ to roles/
- Update roles_path in ansible.cfg
- Add cast user to common role
- Create standalone podman role
- Add semaphore role with Podman + Quadlet support

ansible/roles/step-ca/handlers/main.yml

@@ -0,0 +1,7 @@
+---
+# file: roles/step-ca/handlers/main.yml
+
+- name: restart step-ca
+  community.docker.docker_compose_v2:
+    project_src: "{{ stepca_base_dir }}"
+    state: restarted