addOnAuthenticatedCallback abstract method
Add a callback to be invoked when user authenticates.
The callback receives the user's UID (or null if unavailable).
priority determines execution order:
- Higher values execute first (priority 100 runs before priority 0)
- Same priority callbacks execute in parallel
- Default is 0
Implementation
void addOnAuthenticatedCallback(
Future<void> Function(String? uid) callback, {
int priority = 0,
});