Modernize Ansible Roles for Current Ansible Releases and Ubuntu 25 Compatibility

[mryashlk]

Modernize our Ansible roles to ensure clean installation with current Ansible releases and full compatibility with Ubuntu 25. All deprecated functionality has been removed, including:

• Legacy include statements replaced with import_playbook.
• The deprecated get_md5 flag in the stat module removed in favor of get_checksum.

The API orchestrator role now includes explicit Ubuntu 25 defaults as well as fallback values. These defaults and fallbacks are applied consistently across tasks that interact with HAProxy directories or services.

For database provisioning, the role now installs both debconf-utils and python3-pexpect, resolving MariaDB debconf configuration issues on Debian-based systems. Additionally, the RabbitMQ role now remaps Ubuntu "questing" releases (24.10/25.x) to jammy to ensure the correct apt repository configuration.

Related to #565

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