login form works, the state update after that almost - CORRECT COMMIT

backend/src/main/java/hu/pazmany/DocumentDto.java

backend/src/main/java/hu/pazmany/UserService.java

frontend/src/App.vue

frontend/src/components/TheWelcome.vue

frontend/src/components/header-komponens.vue

frontend/src/components/intro-komponens.vue

frontend/src/components/loginform.vue

frontend/src/components/pelda-komponens.vue