When running "expo prebuild", then "npm start" no longer works properly

So I’m trying to add Notifee to my app: https://notifee.app/react-native/docs/installation#expo-support

Notifee has a built-in expo plugin you can install into an Expo managed project.

The instructions get me to run “expo prebuild” and then “expo run:android”. I’m not entirely sure what these commands do, but it seems they make the project not Expo Managed!

After I run “npm start” as usual, the result is this:

Metro waiting on com.pldilley.ticko://expo-development-client/?url=http%3A%2F%2F10.0.0.239%3A8081

And then Expo Go no longer works, the app neither loads in an emulator nor on a phone.