[BUG] Standardize output format of NBeats and NBeatsKAN estimators

[sanskarmodi8]

This PR updates the NBeatsAdapter to ensure that both NBeats and NBeatsKAN models return 3D tensors (batch_size, prediction_length, 1) for point predictions, aligning with the expected output format #1975.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
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Additional details and impacted files

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  Coverage        ?   86.77%           
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  Files           ?      160           
  Lines           ?     9475           
  Branches        ?        0           
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  Hits            ?     8222           
  Misses          ?     1253           
  Partials        ?        0           

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pytest	86.77% <ø> (?)

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[sanskarmodi8]

I'm not sure why this particular test is failing in CI. When I run pytest -k "test_integration and NHiTS" -v locally, it passes without any errors.

[PranavBhatP]

The tests are passing because it is currently skipped for NBeats and NBeatsKAN. Go to their respective package files namely NBeats_pkg and NBeatsKAN_pkg and remove the test skip tag at the bottom of _tags.

[PranavBhatP]

When I run pytest -k "test_integration and NHiTS" -v

The model we are concerned about is NBeats not NHiTS right...

[sanskarmodi8]

When I run pytest -k "test_integration and NHiTS" -v

The model we are concerned about is NBeats not NHiTS right...

Ah yes, you’re right—my bad! The test I ran locally was for NHiTS, but the model in my PR is NBeats. I just wanted to check that the changes I made didn’t break the workflow for a similar model.

[PranavBhatP]

Thanks for the changes!

[sanskarmodi8]

Hey, just wanted to check if there’s anything else needed from my side before it can be merged. Thanks!

[phoeenniixx]

Thanks!