join
suspend fun join(create: Boolean = false, createOptions: CreateCallOptions? = null, ring: Boolean = false, notify: Boolean = false, hintHighScaleLivestreamPublisher: Boolean? = null, callJoinInterceptor: CallJoinInterceptor? = null): Result<RtcSession>
Joins the call. Concurrent callers share one in-flight attempt.
Cancelling this coroutine does not abort that attempt — only leave does.
Join flags (create, ring, and the rest) come from the caller that created the in-flight attempt. CallJoinInterceptor is first-non-cancelled-wins: the first waiter whose coroutine is not cancelled supplies it. A later join(interceptor) is used only if every earlier waiter has been cancelled. join(null) does not erase an earlier interceptor.