@type t() :: %Weld.Manifest.Docs{
  assets: %{optional(String.t()) => String.t()},
  extra_titles: %{optional(String.t()) => String.t()},
  groups_for_extras: [{String.t(), [String.t()]}],
  homepage_url: String.t() | nil,
  logo: String.t() | nil,
  main: String.t(),
  source_ref: String.t() | nil,
  source_url: String.t() | nil
}