Add py.typed type hint marker

[bact]

To indicates that this package supports typing.

This will silent linter warning of "import-untyped" when importing spdx_python_model.

More about py.typed marker
https://peps.python.org/pep-0561/

[benjarobin]

I do not fully agree with this change. There is a lot of information missing.
For example the software_Package class (this is the case for any element) has the following properties: software_downloadLocation, software_packageUrl, software_packageVersion, ...
But all static analysis tools cannot see these properties.
This is going to break all the tools that depend on this library and which are using mypy. Please do not merge that (now)!

The proper solution would be to provide a generated .pyi !

[bact]

@benjarobin for pyi stub, see JPEWdev/shacl2code#74

[bact]

We need BOTH the .pyi stub and the py.typed marker btw.

According to Python typing guide
https://typing.python.org/en/latest/guides/libraries.html

As specified in PEP 561, tools will not treat your package as providing type information unless it includes a special py.typed marker file.

So we need these changes:

1. generate pyi stub Generate Python type stub - allowing more code completion in IDE JPEWdev/shacl2code#74
2. release new schacl2code version
3. update schacl2code version in spdx-3-model
4. copy pyi stub to module path Copy stubs to bindings path after generation at build #18
5. add py.typed marker Add py.typed type hint marker #14 (this PR)
6. release new spdx-python-model version

In that order (or maybe not in that exact order; but 2 must be after 1, and 3, 4, 5 must be after 2 and before 6).

[benjarobin]

We need BOTH the .pyi stub and the py.typed marker btw.

Oh, I see, sorry about that. I was persuaded this was not necessary if the package provided stub files.

generate pyi stub Generate Python type stub - allowing more code completion in IDE JPEWdev/shacl2code#74

Thank you so much for working on that part ! I did not see it. I would have saved a lot of time when developing sbom-cve-check. Again thank you!

But maybe you should "merge" this pull request with #18
I think you could close this one and add a commit to #18 that adds the py.typed file.

[bact]

But maybe you should "merge" this pull request with #18 I think you could close this one and add a commit to #18 that adds the py.typed file.

True. Better that way, so relevant changes are kept together. Thank you for the suggestion.