Add owner role and admin management controls

wwwroot/js/state.js

@@ -1,5 +1,6 @@
 export const state = {
     isAuthenticated: false,
+    ownerExists: false,
     authMode: "login",
     me: null,
     phase: null,
@@ -19,6 +20,7 @@ export const state = {
 };
 
 export function clearUserState() {
+    state.ownerExists = false;
     state.me = null;
     state.phase = null;
     state.prevPhase = null;