Fix cp and not per token loss calculation in schedules.py

[wplf]

Updated loss calculation to use all-reduced token count and adjusted output tensor accordingly.

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flowchart LR
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[asolergi-nv]

@greptile Please review

[greptile-apps]

_{1 file reviewed, 3 comments}

_{Edit Code Review Agent Settings | Greptile}

[wplf]

Sry about my silly mistake.
@greptile Please review again.

[wplf]

@greptile Please review again.