Module cluster 

Structs

GracefulShutdown

Graceful shutdown coordinator.

HeartbeatConfig

Heartbeat loop configuration.

HeartbeatLoop

Heartbeat loop for cluster health.

InFlightGuard

RAII guard for tracking in-flight requests.

LeaderConfig

Leader election configuration.

LeaderElection

Leader election using PostgreSQL advisory locks.

LeaderGuard

RAII guard for leader-only operations.

NodeCounts

Node count statistics.

NodeRegistry

Node registry for cluster membership.

ShutdownConfig

Graceful shutdown configuration.