Added sse and a new screen

frontend/src/composables/useServerEvents.js

@@ -0,0 +1,17 @@
+// import useStore from '../store'
+
+export default () => {
+  // const store = useStore()
+
+  const evtSource = new EventSource(`${process.env.VUE_APP_BACKEND}/stream`);
+
+  function addAnswerListener(handler) {
+    evtSource.addEventListener('answer', (event) => handler(JSON.parse(event.data)))
+  }
+
+  function addUserlistListener(handler) {
+    evtSource.addEventListener('userlist', (event) => handler(JSON.parse(event.data)))
+  }
+
+  return { addAnswerListener, addUserlistListener }
+}