Introduce a new WebSocket package implementing RFC6455 functionality and permessage-deflate support. Adds core connection handling (packages/websocket/websocket.js), client wrapper (client.js), server and upgrade handling (server.js), extensions (permessage-deflate) and helpers (extensions.js), an index and native loader (native.js). Also include prebuilt native addon binaries for multiple platforms and integration points to use the native Parser and frame builder. The server supports handleUpgrade, subprotocol negotiation, and verifyClient hooks; the client performs handshakes and queues sends until open. Error handling, UTF-8 validation, close/ping/pong control frames, and max-payload checks are implemented.
