Correctly template in Jitsi widget auth if such exists

Also add roomId to the widget data and URL template. It's needed by
the Element Web Jitsi code to produce auth for the Jitsi backend.

src/CallHandler.js

@@ -405,13 +405,12 @@ async function _startCallApp(roomId, type) {
         confId = `JitsiConference${generateHumanReadableId()}`;
     }
 
-    let widgetUrl = WidgetUtils.getLocalJitsiWrapperUrl();
+    let widgetUrl = WidgetUtils.getLocalJitsiWrapperUrl({auth: jitsiAuth});
 
     // TODO: Remove URL hacks when the mobile clients eventually support v2 widgets
     const parsedUrl = new URL(widgetUrl);
     parsedUrl.search = ''; // set to empty string to make the URL class use searchParams instead
     parsedUrl.searchParams.set('confId', confId);
-    parsedUrl.searchParams.set('auth', jitsiAuth);
     widgetUrl = parsedUrl.toString();
 
     const widgetData = {
@@ -419,6 +418,7 @@ async function _startCallApp(roomId, type) {
         isAudioOnly: type === 'voice',
         domain: jitsiDomain,
         auth: jitsiAuth,
+        roomId: roomId,
     };
 
     const widgetId = (