fix(operator): persist worker hash in DGD status

[tmonty12]

Summary

• Make status.currentWorkerHash the authoritative completed v2 worker hash, while retaining the v2 annotation as a downgrade-compatible mirror.
• Backfill status from existing v2 annotations and restore an unambiguous legacy v1 DCD suffix when a replacement strips controller-owned annotations.
• Update status on initial, unsupported-pathway, migration, and completed-rollout hash commits; preserve the target annotation while an in-progress rollout retries its central status write.
• Expose the field in both served DGD API versions and CRD schemas.

Fixes #13495

Validation

• Focused worker rollout controller tests passed.
• API v1alpha1 and v1beta1 package tests passed.
• Verified both DGD CRD versions expose status.currentWorkerHash as a string.

The unrestricted controller package suite was not run because this isolated worktree lacks the envtest etcd binary.

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