static isLazy(fn, target) {
		if (typeof fn !== "function") return false;
		const t = fn[LAZY_TARGET];
		return target ? t === target : Boolean(t);
	}
@template {LazyTarget} TLazyTarget
@param {EXPECTED_ANY} fn lazy function
@param {TLazyTarget=} target target middleware
@returns {fn is LazyFunction<EXPECTED_ANY, EXPECTED_ANY, TLazyTarget, EXPECTED_ANY>} true, when fn is a lazy function (optionally of that target)