Refactor Ansible playbooks to comply with best practices and fix linting violations

- Implement 4-role architecture (base_provision, patching, hardening, decommission)
- Extract hardcoded values to role defaults and group_vars
- Add Ansible Vault integration for secrets management
- Implement proper handlers for service restarts instead of direct tasks
- Add Molecule testing framework with Docker driver
- Configure ansible-lint with production profile settings

Fix all 125+ ansible-lint violations:
- Add FQCN (Fully Qualified Collection Names) to all modules
- Replace yes/no with true/false for boolean values
- Add explicit mode parameters to file/template operations
- Remove duplicate post_tasks blocks from playbooks
- Add newlines at end of all YAML files
- Fix key ordering in tasks (name, when, block)
- Convert service restarts to handlers with notify
- Remove ignore_errors in favor of failed_when/changed_when
- Fix line length violations and empty lines
- Add noqa comments for unavoidable risky-file-permissions

Update documentation:
- Add REFACTORING.md with implementation details
- Add VAULT_GUIDE.md for secrets management
- Add per-role README.md files
- Update existing documentation

All playbooks now pass ansible-lint production profile with 0 violations.

enterprise-infra-simulator/roles/hardening/defaults/main.yml

@@ -0,0 +1,35 @@
+---
+# Hardening configuration
+cis_level: 1
+disable_root_login: true
+secure_ssh_config: true
+firewall_policy: deny
+auditd_enabled: true
+selinux_mode: enforcing
+apparmor_enabled: true
+
+# SSH Hardening
+ssh_max_auth_tries: 3
+ssh_client_alive_interval: 300
+ssh_client_alive_count_max: 2
+
+# Firewall rules for SSH (trusted networks)
+ssh_allowed_networks:
+  - 10.0.0.0/8
+  - 172.16.0.0/12
+  - 192.168.0.0/16
+
+# Services to disable
+unnecessary_services:
+  - cups
+  - avahi-daemon
+  - bluetooth
+  - nfs-server
+  - rpcbind
+
+# Packages to remove
+unnecessary_packages:
+  - telnet
+  - rsh-client
+  - talk
+  - ntalk