Add --node-deployment flag for distributed resizing

[mnencia]

What type of PR is this?

/kind feature

What this PR does / why we need it:

For CSI drivers deployed as DaemonSets managing node-local volumes, there is no central controller pod where a centralized external-resizer can run. The provisioner and snapshotter sidecars already support --node-deployment for this deployment model.

This adds the same capability to the external-resizer. When enabled, each instance only processes resize requests for PVs whose nodeAffinity matches the local node. The flag requires NODE_NAME env var and is mutually exclusive with --leader-election.

The filtering is applied in the controller (pvNeedResize and pvCanBeExpanded), covering both Resizer implementations without changes to the Resizer interface.

Which issue(s) this PR fixes:

Fixes #142

Special notes for your reviewer:

This is a fresh implementation building on the prior work by @travisghansen in #195 (closed by triage bot), with two key differences:

1. Filtering location: applied in the controller rather than in CanSupport, so it covers both the csiResizer and trivialResizer code paths.
2. Filtering mechanism: uses PV nodeAffinity instead of the PVC volume.kubernetes.io/selected-node annotation, which is cleared by the provisioner after binding and would not be available at resize time.

The pvBelongsToNode helper checks MatchExpressions with NodeSelectorOpIn operator, which is what CSI provisioners use when translating AccessibleTopology segments into PV node affinity. Other operators (NotIn, Exists, etc.) and MatchFields are intentionally not handled, as they are not used by CSI drivers for node-local topology.

The modify controller (VolumeAttributesClass) is not covered by node filtering in this PR. Node-local CSI drivers typically do not use VolumeAttributesClass, so this is not blocking for the primary use case and can be addressed in a follow-up.

See also kubernetes-csi/csi-driver-host-path#651 for the downstream consumer of this feature.

Does this PR introduce a user-facing change?:

Add --node-deployment flag to enable distributed resizing for CSI drivers managing node-local volumes in DaemonSet deployments.

[k8s-ci-robot]

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[mnencia]

I have a working integration of this at dev/651-with-resizer on csi-driver-host-path, adding the csi-resizer with --node-deployment=true to the distributed DaemonSet deployment. Tested on a 3-node Kind cluster with volume expansion working correctly (including the node-filtering logic skipping non-local PVs as expected). That branch depends on this PR being merged. Related to #142.