- Rename package/module from toki_socket to proto_socket in Dart, Kotlin, Python
- Update crosstest implementations to use renamed packages
- Add new proto_socket skill, deprecate add-toki-socket-crosstest-language skill
- Update domain rules for all languages
- Update documentation (README, PORTING_GUIDE, PROTOCOL, VERSIONING)
- Dart: Add BaseClient<Self> to eliminate duplicate code
- Dart: Replace dispose() with close() (Future<void> return)
- Dart: Make isAlive and nonce read-only with @protected setter
- Dart: Add meta package dependency for @protected
- Dart: Implement BaseClient<ProtobufClient> and BaseClient<WsProtobufClient>
- Dart: Update communicator.dart with private fields and protected setters
- Dart: Update heartbeat_mixin.dart for new close() pattern
- Dart: Update all client/server implementations
- Dart: Update test files with new API
- Dart: Export base_client.dart in toki_socket.dart