[FR] File Locations in SPDX SBOM for language packages

The file location is not present in SPDX output. It would be useful to have this information in the SPDX SBOM to id files and figure out where it's installed within the filesystem.

Start by tracing how this Go repository produces SPDX SBOM output and how language packages are represented. Add file-location information that identifies package files and their installation paths, then verify that the generated SPDX output contains those locations.

Written by the indexing model from the issue text.