:sig
String ws_connection_id()

:params
return value : connection ID of the current WebSocket client

:see
>websocket

:content
Returns the runtime-generated connection ID of the client whose message is currently being handled.

This ID can be passed to `ws_send_to()` or `ws_close()` to target a single connected client.

:example
String id = ws_connection_id();
print(id == "" ? "(empty outside a WS handler)" : id, "\n");
