[QA Fix] fix(data): apply the null-content contract to legacy chat turns #6398

Summary

This retrospective issue records a bug fixed by QA in NVIDIA-NeMo/Megatron-Bridge.

Fix record

• QA fix owner: @pruprakash
• Resolved by merged PR: fix(data): apply the null-content contract to legacy chat turns #5742
• Fix branch: pruprakash/fix_data_sharegpt_null_value_content
• Merge commit: 79c2b8cf447173bb813a67efe5c598c592020694
• Merged: 2026-10-06

Delivered fix

fix(data): apply the null-content contract to legacy chat turns

Resolution

The change and its validation are documented in PR #5742.

This issue is being closed as completed because PR #5742 is already merged.