RHV templates unsupported by get_per_nic_networks() / per_nic_network_map

[krcmarik]

Summary

get_per_nic_networks() in utilities/utils.py (around line 228) explicitly raises a ValueError when called with RHV template names that haven't been cloned into VMs yet, since RHV templates aren't present in the Forklift inventory. This means per_nic_network_map=True currently cannot work for RHV plans before cloning.

Problem / Motivation

get_per_nic_networks() needs deduplicate=False semantics, but BaseProvider.get_vm_or_template_networks() does not support that option. As a workaround, the function queries inventory directly and special-cases RHV by raising a ValueError for RHV template names, since RHV templates aren't present in Forklift inventory until they are cloned into VMs.

This directly affects the multus_network_name fixture in conftest.py, which computes NAD counts from un-cloned template names -- for RHV plans, this computation cannot succeed today.

The limitation is currently dormant and untested: the only test exercising per_nic_network_map=True is tests/cold/test_dual_nic_cold_migration.py::TestColdDualNicSameNetworkPlanValidation, which is marked @pytest.mark.vsphere and does not target RHV. So the bug is latent rather than actively breaking CI.

Requirements

1. Extend the BaseProvider.get_vm_or_template_networks() contract with a per-NIC / deduplication option (e.g. a deduplicate parameter).
2. Implement the new option in each provider that subclasses BaseProvider (RHV in particular, plus the other providers for consistency).
3. Update get_per_nic_networks() in utilities/utils.py to delegate through the provider abstraction (get_vm_or_template_networks()) instead of querying inventory directly and special-casing RHV.
4. Remove the ValueError special-case for RHV template names once RHV support is implemented.
5. Extend or add test coverage for per_nic_network_map=True against RHV plans (in addition to the existing vSphere-only coverage).

Deliverables

• Code changes to BaseProvider and provider implementations (RHV and others as needed)
• Code changes to get_per_nic_networks() in utilities/utils.py
• README update (if applicable)
• CLAUDE.md update (if applicable)
• Tests covering per_nic_network_map=True for RHV plans

Notes

• This limitation spans 5 providers implementing BaseProvider, so the fix requires a broader contract change rather than a localized patch.
• Originally raised as a CodeRabbit automated review comment on PR feat(MTV-692): add dual-NIC same-network plan validation test #619 (feat(MTV-692): add dual-NIC same-network plan validation test #619), but deferred at the time since it is not exercised by any current test.