Complete production-ready Caddy infrastructure with security hardening

- Add comprehensive Caddy role with HTTPS/TLS, DNS challenges, and systemd security
- Implement optimized systemd overrides with enhanced security restrictions
- Create detailed documentation with usage examples and variable references
- Establish proper Ansible configuration with vault integration
- Update site.yml for infrastructure orchestration with role-based deployment
- Add host-specific configuration structure for scalable multi-environment setup

ansible.cfg

@@ -0,0 +1,9 @@
+[defaults]
+inventory = inventory/hosts.yml
+host_key_checking = False
+remote_user = root
+deprecation_warnings = False
+vault_password_file = vault-password-file
+
+[ssh_connection]
+ssh_args = -o ControlMaster=auto -o ControlPersist=60s