:sig
String ws_message()

:params
return value : payload of the current WebSocket message

:desc
Returns the payload of the current WebSocket message being handled by `WS()`.

For text frames this is the decoded text payload. For binary frames this String contains the raw message bytes.

Use `ws_is_binary()` or `ws_opcode()` to decide how the payload should be interpreted.

:see
>websocket
