@type mode() :: :duplex | :turn_based

@type state() :: %{
  session_id: String.t(),
  run_id: String.t(),
  mode: mode(),
  status: atom(),
  seq: non_neg_integer(),
  keep_alive: boolean(),
  end_turn_requested: boolean(),
  resume_mapper: (String.t(), map() -> map()),
  stt_adapter: module(),
  stt_pid: pid(),
  tts_adapter: module(),
  tts_pid: pid(),
  tts_buffer: String.t(),
  latest_partial: String.t() | nil,
  latest_final: String.t() | nil,
  turn_started_at: integer() | nil,
  latency: map()
}