@spec find_leader(term()) :: {:ok, RaftEx.Types.server_id()} | {:error, term()}

Find the current leader for a given cluster name.

First checks the local Leaderboard, then queries a member server.

@spec form_cluster(term(), RaftEx.Machine.machine(), [node()], keyword()) ::
  {:ok, [RaftEx.Types.server_id()]} | {:error, term()}

Form a distributed Raft cluster across multiple nodes.

This is the primary entry point for multi-node cluster formation. Each node should call this with the same set of participating nodes.

Parameters

• cluster_name - name for this Raft cluster
• machine - the state machine configuration {:machine, Module, args}
• nodes - list of participating Erlang nodes (including self)
• opts - optional keyword list:
  • :system - RaftEx system name (default: :default)
  • :timeout - timeout in ms (default: 10_000)
  • :seed_node - node to act as seed (default: first node in sorted list)

Returns {:ok, local_server_ids} or {:error, reason}.

@spec handle_topology_change([node()], term(), RaftEx.Machine.machine()) :: :ok

Handle a topology change event from NodeDiscovery.

When new nodes are detected, attempts to add them as cluster members.

@spec join_cluster(term(), RaftEx.Machine.machine(), [node()], node(), keyword()) ::
  {:ok, [RaftEx.Types.server_id()]} | {:error, term()}

Join an existing Raft cluster as a new node.

@spec status(atom()) :: {:ok, list()} | {:error, term()}

Get the status of all RaftEx servers on this node.