docs(launcher): scope CLAUDE.md "new model config" section to Megatron-LM PTQ

[h-guo18]

What does this PR do?

Type of change: docs

The "Adding a New Model Config" section in tools/launcher/CLAUDE.md is written for the Megatron-LM PTQ pipeline specifically — its env vars (MLM_MODEL_CFG, QUANT_CFG) only apply there. But the generic title and step 1's megatron_lm_ptq.yaml filename were being read as universal:

• CodeRabbit recently flagged a streaming EAGLE3 yaml (PR #1509) for "missing" MLM_MODEL_CFG / QUANT_CFG, citing this section as the authoritative guideline.
• Empirically, no other tools/launcher/examples/** yaml sets these vars (HF PTQ, HF / offline / streaming EAGLE3, dflash all use different env conventions).

This PR retitles the section to make scope explicit and adds a one-line lead-in pointing other pipelines at sibling yamls as templates.

Before your PR is "Ready for review"

• Backward compatible: ✅ (doc-only)
• New PIP dep: N/A
• New tests: N/A
• Changelog: N/A

Summary by CodeRabbit

• Documentation
  • Updated guidance for adding new Megatron-LM PTQ model configurations with clearer instructions on proper placement and how to copy related pipeline configurations.

[coderabbitai]

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📥 Commits

Reviewing files that changed from the base of the PR and between 6fed3a6 and 909ced4.

📒 Files selected for processing (1)

• tools/launcher/CLAUDE.md

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📝 Walkthrough

Walkthrough

This PR updates the launcher documentation to clarify the process for adding a new Megatron-LM PTQ model configuration. The section heading is scoped from generic "Adding a New Model Config" to specifically "Adding a New Megatron-LM PTQ Model Config," and the instructions now specify the exact YAML location and explain how to derive other pipeline configurations from sibling files.

Changes

Megatron-LM PTQ Configuration Guidance

Layer / File(s)	Summary
Megatron-LM PTQ configuration documentation tools/launcher/CLAUDE.md	Section heading clarified to target Megatron-LM PTQ configs specifically, with guidance on YAML location (examples/<Org>/<Model>/megatron_lm_ptq.yaml) and instruction to base other pipeline configs (HF PTQ, HF/offline/streaming EAGLE3, dflash) on sibling YAML files.

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🎯 1 (Trivial) | ⏱️ ~2 minutes

🚥 Pre-merge checks | ✅ 6

✅ Passed checks (6 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The PR title accurately summarizes the main change: scoping the CLAUDE.md documentation section to be explicitly about Megatron-LM PTQ, which directly matches the single documentation alteration described in the raw summary.
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.
Security Anti-Patterns	✅ Passed	PR only modifies documentation (tools/launcher/CLAUDE.md). No Python code, dependencies, or security anti-patterns detected.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch haoguo/launcher-claudemd-scope

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 76.86%. Comparing base (45893f7) to head (909ced4).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1547      +/-   ##
==========================================
+ Coverage   76.83%   76.86%   +0.03%     
==========================================
  Files         477      477              
  Lines       51954    51954              
==========================================
+ Hits        39917    39934      +17     
+ Misses      12037    12020      -17     

Flag	Coverage Δ
regression	15.24% <ø> (+0.11%)	⬆️
unit	52.76% <ø> (ø)

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