Major protocol update: OnReceiveMessage now takes metadata (SignalReceiveParams) and payload (byte[]) as separate hub arguments, not a single envelope. Metadata is AcBinary-serialized; payload uses protocol fast-path. Updated all client/server code, interfaces, and docs. Added ISignalParams and SignalReceiveParams types. Improved AcBinaryHubProtocol diagnostics and made byte[] fast-path more robust. This enables clearer, more debuggable, and future-proof SignalR binary messaging.
Introduce ArrayBinaryOutput, BufferWriterBinaryOutput, BinaryOutputBase, and IBinaryOutput for flexible, efficient serialization to pooled arrays and streaming buffers. Refactor AcBinaryHubProtocol to use new output for SignalR. Make UseMetadata runtime-settable in AcBinarySerializerOptions. Update QuickBenchmark for new options. Enables allocation-free, extensible binary serialization infrastructure.