Add DocumentDB DC-DR types (status.disasterRecovery, distributed, per-DC HorizontalScaling)

[tamalsaha]

Summary

This is the DocumentDB fan-out of the Postgres cross data center disaster recovery (DC-DR) design. It adds the apimachinery types DocumentDB needs so the operator and coordinator can express distributed multi-DC clusters and report their DR state.

apis/kubedb/v1alpha2/documentdb_types.go

• DocumentDBSpec.Distributed bool (json distributed). When true, the operator expands the CR into per-DC manifestwork objects instead of raw resources.
• DocumentDBSpec.PodPlacementPolicy *core.LocalObjectReference (json podPlacementPolicy, defaults to {name:"default"}).
• DocumentDBStatus.DisasterRecovery *DocumentDBDisasterRecoveryStatus (json disasterRecovery), the cross-DC view reflected onto the single Database object.
• New types: DocumentDBDRPhase (consts Steady, FailingOver, FailingBack, Degraded), DocumentDBDisasterRecoveryStatus (ActiveDC, Phase, DataCenters, LastTransitionTime), and DocumentDBDCStatus (ClusterName, Role, Leader, Writable, LagBytes, Healthy).

apis/ops/v1alpha1/documentdb_ops_types.go

• DocumentDBHorizontalScalingSpec.DataCenters []DocumentDBHorizontalScalingDC (json dataCenters), for scaling each DC's local node count independently.
• New type DocumentDBHorizontalScalingDC (ClusterName, Replicas).

Deepcopy

Hand-edited zz_generated.deepcopy.go in both packages to match the shapes the Postgres generated funcs use (pointer alloc for LagBytes and LastTransitionTime, range copy for DataCenters, LocalObjectReference and DisasterRecovery pointer deepcopy).

Verification

go build ./apis/... and go vet ./apis/kubedb/v1alpha2/... ./apis/ops/v1alpha1/... both pass.

Notes

• CRD and openapi regeneration is intentionally deferred to CI make gen, so status.disasterRecovery and the new spec fields are not yet in the generated schema.
• This is staging step 1 of the DocumentDB DC-DR rollout. It must merge and release before the DocumentDB operator will compile against these types.