clear method
Deletes ALL keys managed by FlutterSecureStorage.
⚠️ This is irreversible – all encrypted values will be permanently lost.
Implementation
Future<void> clear() async {
try {
await _storage.deleteAll();
} catch (e, st) {
throw StorageException(
message: 'Failed to clear secure storage',
cause: e,
stackTrace: st,
);
}
}