delete method
Implementation
Future<void> delete(String recordId) async {
final record = await store.getRecord(recordId);
final clock = record?.clock ?? VectorClock();
clock.increment(deviceId);
final op = Operation(
opId: _generateOpId(),
recordId: recordId,
clock: clock,
isDelete: true,
);
await store.saveOperation(op);
await store.applyOperation(op);
}