As a link clicker, I want to join rooms only with sharing enabled and text chat (no video or audio).

Acceptance criteria:
- When reaching the Hello URL, join the room automatically audio and face muted
--if the link generator is in the room then the link clicker can do text chat, see his shared tabs (if not paused) and see/hear him (if not audio/face muted)
--if the link generator is NOT in the room then the link clicker is in waiting state
- Unmuting the camera turns on both the mic and camera (through gUM door hanger)
- Unmuting the mic only turns on the mic (through gUM door hanger)