fix: keep events order

[theomonnom]

• Always ensure we keep the order from the FfiServer
  • So the complex logic can be handled from Rust (for synchronisation)
  • E.g: the ffi server ensure that the LocalTrackPublished callback is sent before the LocalTrackPublished event
• We know use only one FfiQueue per room (So it is possible for us to keep things synchronised)

The room musts be used inside one event_loop (specified inside the ctor) AudioStream & VideoStream can be used on other event_loops (making it easy to have another IO thread for e.g)

[theomonnom]

it's tricky, now with the changes, we can't publish tracks before running room.run() ...