feat(vm_healthcheck): add VM health validation role

[stevefulme1]

Summary

Adds a new vm_healthcheck role that performs comprehensive health validation checks on Virtual Machines running in OpenShift Virtualization.

Checks performed

• Status: VM phase (Running), Ready condition, guest agent presence, node assignment
• Networking: Interface IP assignment, interface name consistency, masquerade pod network, bridge/multus attachment
• Storage: PVC bound status, DataVolume succeeded status, volume attachment verification
• Resources: CPU/memory requests vs limits, node capacity, overcommit detection

Deliverables

• roles/vm_healthcheck/ - Full role with defaults, vars, tasks, templates, tests, meta, README
• playbooks/vm_healthcheck.yml - Playbook to invoke the role
• HTML report template for healthcheck results

Testing

• ansible-lint --profile production passes with 0 errors (warnings are yaml[line-length] which is in warn_list)
• All task names use FQCNs (kubernetes.core.k8s_info, ansible.builtin.set_fact, etc.)
• Loop variables use __vm_healthcheck_ prefix per loop_var_prefix config
• Code style matches existing vm_lifecycle role patterns