feat: support DRA admin access in the device allocator

[yindia]

Fixes #3230

Description

Admin-access ResourceClaim requests (KEP-5018) can bind to devices that are already allocated and do not consume them. This wires that behavior into the device allocator:

• Admin-access requests treat already-allocated devices as eligible placement options, instead of skipping them.
• Admin-access allocations no longer count as consuming a device, so other claims can still use it.
• Existing admin-access allocations read from the cluster are ignored the same way.

As a result, Karpenter does not provision extra nodes for admin-access pods that fit hardware already in use.

How was this change tested?

• Allocator unit tests: bind to allocated devices, ignore counters and capacity, and keep device distinctness and selector matching.
• deviceallocation controller unit tests: skip admin-access results.
• Provisioning integration tests: an admin-access pod binds to a held device on an existing node with no new NodeClaim, while an equivalent normal claim launches one.
• go test ./pkg/scheduling/dynamicresources/... ./pkg/controllers/dynamicresources/... ./pkg/controllers/provisioning/... on envtest 1.35. Pre-existing Consumable Capacity failures are unrelated; they need the DRAConsumableCapacity apiserver feature gate.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[kubernetes-prow]

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This pull-request has been approved by: yindia
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