refactor: restructure inventory, split roles and add new services

roles/zerotier-one/handlers/main.yml

@@ -0,0 +1,10 @@
+---
+- name: reload nftables
+  ansible.builtin.command: nft -f /etc/nftables.conf
+
+- name: restart zerotier-one systemd service unit
+  ansible.builtin.systemd_service:
+    name: zerotier-one
+    daemon_reload: true
+    state: restarted
+    enabled: true