submitBulkMemberSaves
protected static void submitBulkMemberSaves(Player player, Collection<? extends CompletableFuture<Void>> saves, String reloadingMessage, String contentType)
Queues a batch of member-configuration saves for the shared end-of-tick flush. The first submission of a tick schedules the flush; later same-tick submissions (meta children) join it. The flush completes every save without blocking the server thread, then hands feedback and the single plugin reload back to the main thread. Tolerates a null player (console/automation).