The same here for my complex playground at https://github.com/gui-dos/DiaBLE/tree/main/DiaBLE%20Playground.swiftpm. Any modification to an app setting disrupts Package.swift: I am importing the CryptoSwift package and the "AppModule" .executableTarget is removed and replaced by the CryptoSwift library and test targets.

My app https://github.com/gui-dos/DiaBLE is independent and I am succeeding in keeping it in the background while communicating with the glucose sensor Libre 3 which reconnects very regularly every minute. I am setting a smart alarm at 55 seconds even though I am not supporting real workout activities yet... B-)