A cost record linked to a conversation turn.
Records the token usage and computed cost for a single AI provider
call, using Decimal for all monetary values.
Summary
Types
@type t() :: %PhoenixAI.Store.CostTracking.CostRecord{ conversation_id: String.t(), id: String.t() | nil, input_cost: Decimal.t(), input_tokens: non_neg_integer(), metadata: map(), model: String.t(), output_cost: Decimal.t(), output_tokens: non_neg_integer(), provider: atom(), recorded_at: DateTime.t() | nil, total_cost: Decimal.t(), user_id: String.t() | nil }