Refactor WebSocket message interfaces

Changes:
- Replace AccountTextMessage with an extendable ContactMessage interface
- Add accountId parameter to server-side WebSocket callbacks
- Set the accountId for WebRTC messages on server-side for security
- Rename all WebRTC and SDP variables to proper camelCase or PascalCase

GitLab: #147
Change-Id: I125b5431821b03ef4d46b751eb1c13830017ccff
diff --git a/client/src/pages/ChatInterface.tsx b/client/src/pages/ChatInterface.tsx
index f226fec..f30c15a 100644
--- a/client/src/pages/ChatInterface.tsx
+++ b/client/src/pages/ChatInterface.tsx
@@ -88,12 +88,13 @@
 
   useEffect(() => {
     if (webSocket) {
-      const conversationMessageListener = ({ message }: ConversationMessage) => {
+      const conversationMessageListener = (data: ConversationMessage) => {
         console.log('newMessage');
-        setMessages((messages) => addMessage(messages, message));
+        setMessages((messages) => addMessage(messages, data.message));
       };
 
       webSocket.bind(WebSocketMessageType.ConversationMessage, conversationMessageListener);
+
       return () => {
         webSocket.unbind(WebSocketMessageType.ConversationMessage, conversationMessageListener);
       };