Investigate Background Bean Initialization

[SentryMan]

It seems spring has added background initialization as a core DI feature.

Something like this would synergize well with beans that take some time to construct, allowing for other beans to be wired during the same time.

[SentryMan]

My initial thought is to generate background beans like this

@Generated("io.avaje.inject.generator")
public final class BackgroundBean$DI  {

  public static void build(Builder builder) {
    if (builder.isAddBeanFor(BackgroundBean.class)) {
      builder.registerProvider(CompletableFuture.supplyAsync(() -> {
        var bean = new BackgroundBean();
        return bean;
      })::join); 
    }
  }
}