I understand that annotations like @UsesPermissions allow to add the necessary information to the application manifest XML model. Does the AppInventor add these annotations at the moment of the extension is loaded?
I believe(I have 0 actual knowledge of this) that they are added to the manifest when the .apk is being compiled.
I think you should ask this question in the Open Source Category of Appinventor.
Annotations basically reduce coding and contains processing logic that is used at compile time to generate your apk or extension
I ask because I wanted to try adding service registration to the manifest. It seems that the service cannot be registered dynamically.