Websocket refactor: Pull it out of the UI and support callbacks (#104)

* Websocket refactor: Pull it out of the UI and support listeners

* Changes required for Safari to be happy with modules

* Move to explicit ad-hoc callback registration

webroot/index.html

@@ -181,16 +181,16 @@
 
   <script src="js/usercolors.js"></script>
   <script src="js/utils.js?v=2"></script>
-  <script src="js/message.js?v=2"></script>
+  <script type="module" src="js/message.js?v=2"></script>
   <script src="js/social.js"></script>
   <script src="js/components.js"></script>
-  <script src="js/player.js"></script>
-  <script src="js/app.js?v=2"></script>
-  <script>
-    (function () {
-      const app = new Owncast();
-      app.init();
-    })();
+  <script type="module">
+      import Owncast from './js/app.js';
+
+      (function () {
+        const app = new Owncast();
+        app.init();
+      })();
   </script>
 
   <noscript>