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/hermes/defaults/main.yml

@@ -0,0 +1,15 @@
+---
+# Hermes service user
+hermes_user: hermes
+hermes_group: hermes
+hermes_home: /home/hermes
+
+# Install flags
+# Set to true if you don't need browser automation (skips Playwright/Chromium)
+hermes_skip_browser: false
+
+# systemd service name
+hermes_service_name: hermes
+
+# Path where hermes binary will be accessible system-wide
+hermes_bin_symlink: /usr/local/bin/hermes