Is there any information if code generation packages like (json_serializable, freezed) are automatically ignored when I build a release version (apk/appbundle) or shall I remove them manually from pubspec.yaml?
build a release version while I am using code generation packages
In pubspec.yaml, there are two sections for the packages your project uses: dependencies and dev_dependencies.
Code generation packages, like the ones you mentioned, typically provide separate packages for dependencies and dev_dependencies. Therefore, you don't need to remove anything manually when building a release version of your app.
For example:
dependencies: # Affects both compilation and runtime
freezed_annotation: ^2.4.4
json_annotation: ^4.9.0
dev_dependencies: # No impact on runtime behavior
build_runner: ^2.4.12
freezed: ^2.5.7
json_serializable: ^6.8.0