@type t() :: %ExMCP.Client.States.Ready{
  capabilities: map(),
  common: ExMCP.Client.States.Common.t(),
  initialized_capability: String.t() | nil,
  next_request_id: integer(),
  pending_requests: %{required(integer()) => term()},
  progress_callbacks: %{required(String.t()) => fun()},
  server_info: map(),
  transport: {module(), term(), pid()},
  transport_state: term()
}