Integrate Libvirt QoS IoTune settings into XML configuration for domain disks

This update integrates Quality of Service (QoS) IoTune settings, available in Libvirt, directly into the disk XML configuration for domain creation when desktop starts. By embedding these QoS parameters, we enable finer control over disk input/output performance, ensuring optimized resource utilization and enhanced operational efficiency for virtual machines. This enhancement is pivotal for scenarios requiring precise disk throughput and bandwidth management. See iotune section in https://libvirt.org/formatdomain.html#devices