message: add scopes documentaiton
diff: @@ -139,8 +139,12 @@ The app private key serves three functions.
  * It is used to create the credentials that give an app access to the gaia hub storage bucket for that specific app.
  * It is used in the end-to-end encryption of files stored for the app on the user's gaia hub.
  * It serves as a cryptographic secret that apps can use to perform other cryptographic functions.
  +
  ## Scopes
  -To be added
  +Scopes define the information and permissions an app requests from the user during authentication. If no `scopes` array is provided to the `redirectToSignIn` or `makeAuthRequest` functions.
  +- `store_write` - read and write data to the user's Gaia hub in an app-specific storage bucket
  +- `publish_data` - publish data so that other users of the app can discover and interact with the user
  +- `email` - requests the user's email if available
  ## Authentication tokens
  