docs(topology): document NVCF-native MNNVL scheduling primitives

[estroz]

TL;DR

This MR documents NVCF's native MNNVL scheduling primitives, in lieu of KAI/Grove usage

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For the Reviewer

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Issues

Relates to #598

Checklist

• I am familiar with the Contributing Guidelines.
• I have signed off my commits for Developer Certificate of Origin (DCO) compliance.
• New or existing tests cover these changes.
• The documentation is up to date with these changes.

Summary by CodeRabbit

• Documentation
  • Documented legacy NVLink partition annotations and their supported workload behavior.
  • Clarified best-effort placement, logical grouping, affinity, and Pod mutation semantics.
  • Added guidance on using gang and topology-aware scheduling for coordinated workload placement.
  • Updated Helm examples with NVLink placement options and scheduler limitations.

[coderabbitai]

📝 Walkthrough

Walkthrough

This PR documents legacy NVLink partition annotations for Helm functions. It describes their Pod-affinity behavior, logical grouping, Pod mutations, and best-effort placement limits. It also updates topology scheduling guidance and a multi-node StatefulSet example.

Changes

Legacy NVLink placement documentation

Layer / File(s)	Summary
Annotation semantics docs/user/helm-functions.md	Documents the required-nvlink-domain-index annotation, logical partition behavior, supported placement semantics, required locations, and NVCA mutations to admitted Pods.
Usage guidance and example docs/user/cluster-management/topology-aware-scheduling.md, examples/function-samples/helmchart-samples/multi-node-helm-function-test/multi-node-test/templates/statefulset.yaml	Documents best-effort placement without KAI Scheduler or Grove and adds corresponding comments to the multi-node StatefulSet example.

Estimated code review effort: 1 (Trivial) | ~5 minutes

Possibly related PRs

• NVIDIA/nvcf#603: Documents related legacy NVLink annotations and KAI/Grove topology-aware alternatives.

Suggested reviewers: vrv3814, kristinapathak

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title uses a valid Conventional Commit format and accurately describes the documentation changes for NVCF-native MNNVL scheduling primitives.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch estroczynski/docs/legacy-nvlink-sched

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[github-actions]

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