feat: initial libvirt domain module for provider v0.9.x

[xnoto]

Summary

• Initial Terraform module for creating libvirt domains (VMs) with cloud-init and optional AAP integration
• Updated to libvirt provider v0.9.x schema (breaking change from previous versions)
• Includes CI workflow for pre-commit tests and GitHub releases on tag push

Usage

module "vm" {
  source = "git::https://github.com/makeitworkcloud/terraform-libvirt-domain.git?ref=v0.1.0"

  name         = "my-vm"
  storage_pool = "default"
  # ... see README for full variable list
}

After merge, tag with v0.1.0 to create first release.