feat(vm): implement CPU/memory hotplug via in-place resize

[yaroslavborbat]

Description

Implement hotplug CPU/Memory via in-place resize (without live migration).

New alpha feature gate added:

• HotplugCPUAndMemoryWithInPlaceResize — CPU and memory hotplug using in-place pod resize

KubeVirt patched to expose the in-place resize capability. The workload-updater controller updated with a new hotplug handler that applies in-place resize when the feature gate is enabled. CPU/memory comparators updated to detect spec changes and trigger reconciliation accordingly.
deckhouse/3p-kubevirt#103

Why do we need it, and what problem does it solve?

The existing hotplug via live migration requires a second node and causes VM downtime during migration. In-place resize allows changing vCPU count and memory of a running VM without migration, reducing overhead and enabling hotplug in single-node environments.

What is the expected result?

1. Enable HotplugCPUAndMemoryWithInPlaceResize feature gate.
2. Edit VirtualMachine spec to change CPU/memory.
3. VM resources are updated without migration or restart.

Checklist

• The code is covered by unit tests.
• e2e tests passed.
• Documentation updated according to the changes.
• Changes were tested in the Kubernetes cluster manually.

Changelog entries

section: vm
type: feature
summary: Add hotplug CPU and memory via in-place resize (alpha, behind feature gate HotplugCPUAndMemoryWithInPlaceResize).

[deckhouse-BOaTswain]

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[deckhouse-BOaTswain]

Workflow has started.
Follow the progress here: Workflow Run

The target step completed with status: failure.

[deckhouse-BOaTswain]

Workflow has started.
Follow the progress here: Workflow Run

The target step completed with status: failure.