/// Unregister a previously-registered `{{ trait_name }}` plugin by name.
/// Removes the plugin from `{{ registry_getter }}()` and stringifies any host error.
pub fn {{ unregister_fn }}(name: String) -> Result<(), String> {
let registry = {{ registry_getter }}();
let mut registry = registry.write();
registry.remove(&name).map_err(|e| e.to_string())
}