feat(sbom): add primary package purpose field for SPDX

[DmitriyLewen]

Description

Add primary package purpose

Checklist

• I've read the guidelines for contributing to this repository.
• I've followed the conventions in the PR title.
• I've added tests that prove my fix is effective or that my feature works.
• I've updated the documentation with the relevant information (if needed).
• I've added usage information (if the PR introduces new options)
• I've included a "before" and "after" example to the description (if the PR is a user interface change).

[DmitriyLewen]

I am not sure about this way.
I had idea: use struct instead of string for Type field.
Something like this:

type Type struct {
	name  string
	isApp bool // true for `jar`, `goBinary`, etc...
}