A thinking content block in an assistant message.
@type t() :: %AmpSdk.Types.ThinkingContent{ extra: map(), thinking: String.t(), type: String.t() }
@spec from_map(map()) :: t()
@spec parse(map() | t()) :: {:ok, t()} | {:error, {:invalid_thinking_content, CliSubprocessCore.Schema.error_detail()}}
@spec parse!(map() | t()) :: t()