Add hugging-face command support

[vycius]

Summary

• Adds a new hugging-face command group backed by the pulp_hugging_face plugin, for managing Hugging Face Hub pull-through caching via Pulp.
• pulp-glue: new entity contexts — PulpHuggingFaceRemoteContext, PulpHuggingFaceRepositoryContext, PulpHuggingFaceRepositoryVersionContext, and PulpHuggingFaceDistributionContext (all gated on hugging_face >= 0.1.0).
• CLI: pulp hugging-face with remote, repository, and distribution subgroups (create/show/list/update/destroy, labels, repository versions).
  • remote adds a write-only --hf-token (never returned in API responses) and a --policy option (immediate/on_demand/streamed) for pull-through caching.
  • distribution supports attaching/detaching a remote or repository via --remote / --repository resource options.
• Registers the plugin entry point in pyproject.toml and adds a deferred-context help-page test case.
• Ships functional bash test scripts for the remote, repository, and distribution command groups.

Notes

• PulpHuggingFaceDistributionContext.preprocess_entity only defaults repository/remote to null on create (partial=False), so partial updates no longer detach an attached remote/repository.
• The distribution update command exposes --base-path, consistent with the other distribution plugins.

Test plan

• make lint typecheck test
• Functional: tests/scripts/pulp_hugging_face/test_remote.sh
• Functional: tests/scripts/pulp_hugging_face/test_repository.sh
• Functional: tests/scripts/pulp_hugging_face/test_distribution.sh

Co-Authored-By: Claude Opus 4.7 noreply@anthropic.com