Refactor systemctl services and categories due to alarm bugs

This commit restructures systemctl service definitions and category mappings.

Motivation: Alarm-related bugs revealed inconsistencies in service and role handling.

Preparation step: lays the groundwork for fixing the alarm issues by aligning categories, roles, and service templates.

roles/sys-timer-cln-bkps/README.md

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+# Cleanup Backups Timer
+
+## Description
+
+This role sets up a systemd timer to schedule the periodic cleanup of old backups. It leverages the sys-ctl-cln-bkps role to perform the actual cleanup operation.
+
+## Overview
+
+Optimized for automated maintenance, this role:
+- Sets a fact for the service name.
+- Integrates with the [sys-timer](../sys-timer/README.md) role to schedule sys-ctl-cln-backups tasks at defined intervals.
+
+## Purpose
+
+The primary purpose of this role is to automate the scheduling of backup cleanup operations using a systemd timer, ensuring that backup storage remains within defined limits.
+
+## Features
+
+- **Timer Scheduling:** Configures a systemd timer to trigger the backup cleanup service.
+- **Role Integration:** Works in conjunction with the sys-ctl-cln-bkps role.
+- **Idempotency:** Ensures the timer tasks execute only once per playbook run.