- Introduce OnlineBackupValidator, while accepts serialized protobuf
frames rather than processing an entire file at once.
- Swift: SignalError.backupValidation was **removed** in favor of
MessageBackupValidationError, which it was essentially redundant
with.
- ChatService will soon be replaced by ChatConnection, currently
experimentally available in Node. (All of the networking-related
APIs are still even more subject to change than the rest of
libsignal.
- The Node library now requires ES2021.
- Methods issuing older AuthCredential formats were deprecated and
will be removed in a future release.
- Support for the CDSI option 'return_acis_without_uaks' was removed;
it was already ignored by the service.
- Further backup validator proto updates and performance improvements,
including use of an extra worker thread for pipelining entire-file
processing. ChatItem errors will now include the dateSent timestamp.
- Further work on both key transparency and libsignal-net.
