docs: add no_access organization member role

[alexpouliquen]

Document the new no_access role for organization members across the relevant pages.

---

Note

Low Risk
Docs-only changes that expand role/value lists and add explanatory text; no runtime behavior or API implementation is modified.

Overview
Documents a new organization-level role, no_access, across the Hub docs, updating role lists from 4 to 5 roles and adding a brief description of when to use it (notably alongside Resource Groups for repo-only access).

Updates the programmatic member-role management guide to include no_access in the described org roles and in the allowed role values for the PUT /api/organizations/{name}/members/{username}/role payload, and aligns Resource Groups docs to mention the expanded role set.

^{Reviewed by Cursor Bugbot for commit a7296d4. Bugbot is set up for automated code reviews on this repo. Configure here.}

[HuggingFaceDocBuilderDev]

The docs for this PR live here. All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.

[Pierrci]

thanks!