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By maintaining a separate committedVoterSet, the system ensures:

• Safety: Only committed voters are guaranteed to participate in quorum decisions and maintain data durability.Observability, automation, and monitoring systems should evaluate quorum health and tolerance based solely on the committed voter set, not on nodes that are still joining or pending commitment.  This ensures that safety decisions—such as whether a quorum is available—remain consistent with Raft guarantees.

• Stability: When the committed and uncommitted voter sets differ, the cluster is in a joint consensus phase.
  Exposing this state allows management and orchestration systems to recognize that the controller quorum is undergoing a transitional reconfiguration, and to avoid assuming the new configuration is already stable.

• Debugging and Compliance Verification: During troubleshooting or post-incident audits, operators and tools must be able to differentiate between committed voters and uncommitted replicas that voters that have started replicating but are not yet officially part of the quorum.This distinction is critical for confirming whether a reconfiguration completed successfully and whether the cluster’s control plane reached a consistent state.

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Committed voter present in current voters/observers
If a committed voter is also present in the current voters or observers set, its ReplicaState is identical to the corresponding entry in those sets. This ensures that all runtime fields within ReplicaState are available and reflect the current replica state.

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Above fields are only meaningful for active replicas(voter) in the quorum. For committed voters, they are not strictly required—the sentinel values simply indicate that the data is unavailable or not applicable.

High watermark is unknown when leader startup

• In such case, the initialize voters should return empty set because we don't know the high watermark.

Compatibility, Deprecation, and Migration Plan

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