refactor: A `Message` now explicitly has a `MessageKey`
[demos/kafka/chat] / src / main / java / de / juplo / kafka / chat / backend / domain /
drwxr-xr-x   ..
-rw-r--r-- 2131 Chatroom.java
-rw-r--r-- 568 Message.java
-rw-r--r-- 396 MessageMutationException.java