lib: fix WebIDL `object` and dictionary type conversion

PR-URL: https://github.com/nodejs/node/pull/37047


Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>