=== Demo 2: @Async-style virtual thread executor + SecurityContext ===
A) MODE_THREADLOCAL, raw SimpleAsyncTaskExecutor(virtual): NO AUTHENTICATION (lost)  [VirtualThread[#23,vt-1]/runnable@ForkJoinPool-1-worker-1]
B) MODE_INHERITABLETHREADLOCAL, raw SimpleAsyncTaskExecutor(virtual): authenticated as bob  [VirtualThread[#26,vt-1]/runnable@ForkJoinPool-1-worker-2]
C) DelegatingSecurityContextExecutor around SimpleAsyncTaskExecutor(virtual): authenticated as carol  [VirtualThread[#27,vt-1]/runnable@ForkJoinPool-1-worker-1]
SecurityContextHolderThreadLocalAccessor present: true
D) ContextPropagatingTaskDecorator on SimpleAsyncTaskExecutor(virtual), no Delegating* wrapper: authenticated as dave  [VirtualThread[#28,vt-1]/runnable@ForkJoinPool-1-worker-1]