Here's a collection of commands to use server powers to do various things. Be careful when using them, I usually find and print an object's state before editing it, since it's very easy to get in a broken state by editing the database directly like that and having the previous values helps in reconstructing it if you mess up.
// Refresh every room's image assets
storage.db.rooms.find().then(rooms => Promise.all(rooms.map(({ _id }) => map.updateRoomImageAssets(_id))));