- Fixed mock service property overrides to match base class properties
- Added missing CryptoKit imports where needed
- Fixed immutable property assignments by creating new instances
- Replaced XCTAssertThrows with XCTAssertThrowsError
- Fixed DeliveryAck serialization method names (serialize -> encode)
- Fixed unused variable warnings
- Ensured all BitchatPacket modifications create new instances
- Fixed BitchatMessage property mutations by creating new instances
All test targets now build successfully for both iOS and macOS platforms.