feat: improve calendar integration and meeting UI

- Refactor ICS sync tasks to use @asynctask decorator for cleaner async handling
- Extract meeting creation logic into reusable function
- Improve meeting selection UI with distinct current/upcoming sections
- Add early join functionality for upcoming meetings within 5-minute window
- Simplify non-ICS room workflow with direct Whereby embed
- Fix import paths and component organization

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

www/app/webinars/[title]/page.tsx

@@ -150,7 +150,15 @@ export default function WebinarPage(details: WebinarDetails) {
 
   if (status === WebinarStatus.Live) {
     return (
-      <>{roomUrl && <WherebyEmbed roomUrl={roomUrl} onLeave={handleLeave} />}</>
+      <>
+        {roomUrl && (
+          <WherebyEmbed
+            roomUrl={roomUrl}
+            onLeave={handleLeave}
+            isWebinar={true}
+          />
+        )}
+      </>
     );
   }
   if (status === WebinarStatus.Ended) {