initialDeepLink static method
The deep link that launched the app, if a widget tap did.
A pull alternative to onDeepLink for routing at startup: read it once
in main before deciding the initial route. Returns null when the app
was opened normally, and clears itself so a later read does not re-route.
Implementation
static Future<String?> initialDeepLink() async {
_ensureInitialized();
final pending = _pendingDeepLink;
_pendingDeepLink = null;
return pending;
}