Regenerate testvm01 configuration using updated create-host templates:
- Boot device now /dev/vda (was /dev/sda)
- Imports ../template2/hardware-configuration.nix (was ../template)
This should fix the GRUB installation error during bootstrap.
Manually restored flake_branch field in terraform/vms.tf since create-host
doesn't manage that field yet.
Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>
