docs(model): republish Nemotron 3.5 Super guides

[cuichenx]

What does this PR do?

Restores publication of the released Nemotron 3.5 Super VL and Nemotron-3.5 Super Text-only guides, reversing the publication restrictions introduced by #6380.

Changelog

• Restore both guides in Sphinx and nightly Fern navigation and Nemotron indexes.
• Remove the temporary redirects and Sphinx exclusions that hid the guides.
• Remove catalog filtering and regenerate Supported Models from the current cards.
• Add regression coverage for both guides, navigation, catalog links, exclusions, and redirect absence.
• Preserve guide content, verification cards, model code, and current main changes.

GitHub Actions CI

Validation completed locally:

• 24 focused model-verification catalog tests passed.
• Catalog generator --check passed.
• All-file pre-commit passed using an isolated pre-commit environment; normal project resolution is blocked by the uninitialized MCore submodule.
• Fern 5.40.0 check: zero errors, one warning.
• git diff --check passed; independent full-diff review found no actionable issues.

Tests used an isolated pytest/PyYAML environment with --confcutdir=tests/unit_tests/doc_consistency to avoid unrelated GPU fixtures. No model execution or verification reruns are required for this docs-only restoration. Live site deployment is not verified locally.

Before your PR is Ready for review

• Read and followed contributor guidelines.
• Updated regression tests.
• Updated documentation.
• Affects optional installed components (not applicable).

Additional Information

Reverses #6380 while retaining subsequent main-branch changes.

[github-actions]

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/review

Add model=claude to use a Claude reviewer (the default is model=codex). mode=light|strict selects the review depth; for example, /review model=claude mode=strict. Comment /review help for all options.

[github-actions]

🌿 Preview your docs: https://nvidia-preview-pr-6482-f0ecbe39c82b.docs.buildwithfern.com/nemo/megatron-bridge

[cuichenx]

/ok to test f0ecbe3