fix: resolve ansible-lint errors

- Quote octal file mode values (0640, 0750 -> '0640', '0750')
- Add 'Prepare' name to prepare.yml play
- Fix truthy value in .gitea/workflows/test.yaml (on -> 'on')
- Use role name 'bind9' instead of path in converge.yml
- Move tags to top-level for Deploy and Validate Configuration block
- Remove unnecessary comments to clean up code
- Ensure all YAML and Ansible files pass ansible-lint production profile

handlers/main.yml

@@ -21,5 +21,5 @@
       ansible_facts.date_time.iso8601_basic_short + '.tar.gz' }}"
     owner: root
     group: root
-    mode: 0640
+    mode: '0640'
   when: bind9_backup_config is defined and bind9_backup_config