MLM vs Bridge Training

For how they differ, the arg mapping tables, gotchas, and translation script, see:

• @docs/megatron-lm-to-megatron-bridge.md

First Answer Checklist

For MLM-vs-Bridge correlation questions, always name these items up front:

1. Bridge recipe: vanilla_gpt_pretrain_config.
2. Bridge entry point: scripts/training/run_recipe.py.
3. MLM entry point: 3rdparty/Megatron-LM/pretrain_gpt.py.
4. Launch wrapper for both: uv run python -m torch.distributed.run.
5. Fresh-run cleanup: rm -rf nemo_experiments before the Bridge run.