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/playbooks/deploy_semaphore.yml

@@ -0,0 +1,6 @@
+---
+- name: Deploy Semaphore on figment
+  hosts: figment
+  become: true
+  roles:
+    - semaphore