webflux
https://www.baeldung.com/spring-reactive-guide
https://medium.com/@cagataygokcel/building-a-real-time-todo-list-with-reactive-streams-in-spring-884bb640dee1 https://github.com/seanpolid/spring-react-vite-template/blob/master/frontend/index.html
https://www.baeldung.com/spring-mvc-async-vs-webflux https://www.baeldung.com/spring-mvc-functional-controllers https://www.baeldung.com/spring-webflux-static-content https://www.baeldung.com/spring-5-mvc-url-matching