Add the path to the user's libs to be copied.

[JSUYA]

If custom_def.prop exists in the native path, it will be parsed and added to USER_LIB_PATH as the path.

[seungsoo47]

LGTM.
I'd like to add one thing.
How do you think about providing build_def.prop template like the project_def.prop?

[JSUYA]

How do you think about providing build_def.prop template like the project_def.prop?

Could you explain that in a bit more detail?
build_def.prop and project_def.prop are features provided by the Tizen CLI.
https://docs.tizen.org/application/tizen-studio/native-tools/project-conversion/

When user SO files exist in the Native Plugin, only the SO files located in the lib, lib/{arch}, and lib/{arch}/{version} paths are packaged together.
This format is maintained in most cases.

I had expected to be able to use it when a separate LIBS was needed.
However, since it is not an official file, I will apply this patch after further consideration.