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/podman/templates/registries.conf.j2

@@ -0,0 +1,13 @@
+unqualified-search-registries = ["docker.io"]
+
+[[registry]]
+prefix = "docker.io"
+location = "docker.io"
+
+[[registry]]
+prefix = "quay.io"
+location = "quay.io"
+
+[[registry]]
+prefix = "ghcr.io"
+location = "ghcr.io"