Julius Marminge
### Problem
Underlying routes need to know when a native modal dismissal or transition has completed so they can present follow-up UI afterwards. The existing route
transitionEnd
event is not the same navigator-wide native completion signal.
In T3 Code, we currently patch
@react-navigation/native-stack
for this.
### Proposal
Expose the native
ScreenStack
onFinishTransitioning
callback as a typed navigator-wide
finishTransitioning: { data: undefined }
event, emitted without a target so every route in the navigator can observe it.
Happy to send a small, event-only PR for this.