@type status() ::
  :active | :paused | :blocked | :usage_limited | :budget_limited | :complete

@type t() :: %Vibe.Goals.Goal{
  created_at: DateTime.t(),
  goal_id: String.t(),
  objective: String.t(),
  session_id: String.t(),
  status: status(),
  time_used_seconds: non_neg_integer(),
  token_budget: pos_integer() | nil,
  tokens_used: non_neg_integer(),
  updated_at: DateTime.t()
}