refactor!: switch hosts variables to a flat layout

inventory/host_vars/actinium/vars.yml

@@ -2,14 +2,5 @@ ansible_become_password: "{{ vault_root_pass }}"
 ansible_host: "{{ vault_ansible_host }}"
 ansible_user: "{{ vault_ssh_user }}"
 
-custom_security:
-  firewall:
-    mangle:
-      drop_privatenets: false
-      policy:
-        forward: accept
-dns:
-  type: "udp"
-  udp: "{{ vault_groups.network.internal }}"
-network: "internal"
-ip_dualstack: false
+security_firewall_mangle_drop_privatenets: false
+security_firewall_mangle_policy_forward: accept