docs: add OIDC auth pointers to primary notebooks [sc-17043]

[emmavdh]

What and why?

Follow-up to documentation PR #1458 / sc-17043.

Adds a short OIDC alternative pointer (with prod docs URLs) to the primary API-key setup notebooks and install templates, and links the dedicated OIDC quickstart notebook to the new docs page:

https://docs.validmind.ai/developer/quickstart/authenticate-with-oidc-device-flow.html

Notebooks updated

• notebooks/quickstart/quickstart_documentation.ipynb
• notebooks/quickstart/quickstart_validation.ipynb
• notebooks/quickstart/quickstart_model_documentation_oidc_device_flow.ipynb
• notebooks/tutorials/development/1-set_up_validmind.ipynb
• notebooks/tutorials/validation/1-set_up_validmind_for_validation.ipynb
• notebooks/templates/install-validmind/_install-initialize-with-development.ipynb
• notebooks/templates/install-validmind/_install-initialize-with-validation.ipynb
• notebooks/templates/install-validmind/_install-initialize-with-monitoring.ipynb

API-key flows remain the default. No use-case notebooks were bulk-converted.

How to test

1. Open each updated notebook and confirm the OIDC pointer appears near the code-snippet / init guidance.
2. Confirm links resolve (docs page will 404 on prod until documentation PR #1458 is released; staging preview: https://docs-staging.validmind.ai/pr_previews/emma/sc-17043-documentation-library-oidc/developer/quickstart/authenticate-with-oidc-device-flow.html).
3. After merge, sync into documentation with make notebooks / make get-source when ready to publish notebook updates on the docs site.

What needs special review?

• Docs URL depends on documentation PR #1458 shipping to prod.
• Intentionally limited to high-traffic setup notebooks/templates; broader use-case notebooks left unchanged.

Dependencies, breaking changes, and deployment notes

• Depends on docs content from docs: ValidMind Library OIDC device-flow authentication [sc-17043] documentation#1458 for the linked page to exist in production.
• After merge, a documentation sync PR may be needed to pull notebook changes into site/notebooks/.

Release notes

Checklist

• What and why
• Screenshots or videos (Frontend)
• How to test
• What needs special review
• Dependencies, breaking changes, and deployment notes
• Labels applied
• PR linked to Shortcut
• Unit tests added (Backend)
• Tested locally
• Documentation updated (if required)
• Environment variable additions/changes documented (if required)

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