/// Construct a `{{ type_alias }}` from Dart callback closures.
/// FRB synthesises a Dart-callable function type for each closure parameter,
/// which is the whole point of taking them as `impl Fn(...) -> DartFnFuture<R>`
/// parameters rather than storing them as `Box<dyn Fn(...)>` fields on an
/// opaque struct (FRB v2 cannot generate callable closure types in that shape).
{% if has_plugin_super -%}
/// `plugin_name` and `plugin_version` are required for the Plugin super-trait.
{% endif -%}
