foctet-wasm — browser WebSocket interop

Drives the WASM FoctetSession as the handshake initiator over a real browser WebSocket against the native websock_message_server responder (tests.md §3.3). Each binary WebSocket message carries one Foctet frame: the handshake control messages, then sealed application messages.

Start the native server first (from the repo root):
cargo run -p foctet-transport --example websock_message_server --features "runtime-tokio transport-websock" -- --role server --addr 127.0.0.1:4460

Idle — press “Run test”.