Close the narrow race where `streamGlobal` launched the subscribeAll
collector and immediately read `lastGlobalSequence()` — events appended
in that window were dropped by the replay=0 SharedFlow before the
collector actually subscribed. Now use a CompletableDeferred barrier
signaled via `onSubscription` (SharedFlow) or `onStart` (cold fallback),
awaited before `bridge.replaySnapshot()`.
Closes the remaining gap on finding #1 from
docs/specs/2026-05-24-review-fixes.
kami
8f20f6aa24