feat: Affinity cache performance improvements

[wikoion]

What type of PR is this?

/kind cleanup

What this PR does / why we need it:

Performance improvements for affinity cache. DeltaSnapshotStore no longer clears its affinity-related node caches on every pod add/remove. Instead, it keeps havePodsWithAffinity and havePodsWithRequiredAntiAffinity incrementally up to date, only invalidating pvcNamespaceMap and nodeInfoList when that is actually necessary. It also updates cached NodeInfo references correctly when a base node is snapshotted for mutation.

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?

NONE

Additional documentation e.g., KEPs (Kubernetes Enhancement Proposals), usage docs, etc.:

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[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: wikoion
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