Typed struct for an FX RFQ quote.
Returns true if the quote has expired.
@type t() :: %ClearBank.Schemas.FxQuote{ buy_amount: String.t() | nil, buy_currency: String.t(), expires_at: String.t(), quote_id: String.t(), rate: String.t(), sell_amount: String.t() | nil, sell_currency: String.t() }
@spec expired?(t()) :: boolean()
@spec from_map(map()) :: t()