feat: provide an ESM build with and without debug

See also: https://github.com/socketio/engine.io-client/commit/00d7e7d7ee85b4cfa6f9f547203cc692083ac61c

Related:

- https://github.com/socketio/socket.io-client/issues/1188
- https://github.com/socketio/socket.io-client/issues/1378