Added an option to specify demo user, will be created on startup if it does not exist

front/src/AppNavBar.vue

@@ -21,13 +21,13 @@
   const appInfo = ref(null);
   const appInfoErr = ref(null);
 
-   async function logInIfDemoMode(demoMode) {
+   async function logInIfDemoMode(demoMode, demoUsername) {
     if (!demoMode) {
       return;
     }
 
     const demouser = ref({
-      username: "demo",
+      username: demoUsername,
       password: ""
     });
     const res = await postLogin(demouser)
@@ -37,7 +37,7 @@
 
   onMounted(() => {
     getAppInfo(appInfo, appInfoErr)
-    .then(() => logInIfDemoMode(appInfo.value.demoMode));
+    .then(() => logInIfDemoMode(appInfo.value.demoMode, appInfo.value.demoUsername));
   })
 </script>