onChanges method
Imports change blobs rebroadcast by the relay.
CRDTDocument.importChanges de-duplicates, so re-delivered blobs are
harmless.
Implementation
void onChanges(RelayChangesMessage message) {
document.importChanges([
for (final blob in message.changes) Change.fromBytes(base64Decode(blob)),
]);
_seqTracker.addRange(
from: message.seq - message.changes.length,
to: message.seq,
);
}