[ENH] xLSTMTime implementation

[phoeenniixx]

Description

This PR tries to implement xLSTMTime based on this paper

see also sktime issue #6793

Checklist

• Linked issues (if existing)
• Amended changelog for large changes (and added myself there as contributor)
• Added/modified tests
• Used pre-commit hooks when committing to ensure that code is compliant with hooks. Install hooks with pre-commit install.
  To run hooks independent of commit, execute pre-commit run --all-files

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 315 lines in your changes missing coverage. Please review.

Please upload report for BASE (main@a884c4d). Learn more about missing BASE report.

Files with missing lines	Patch %	Lines
pytorch_forecasting/models/xLSTMTime/mLSTM/cell.py	0.00%	74 Missing ⚠️
pytorch_forecasting/models/xLSTMTime/sLSTM/cell.py	0.00%	64 Missing ⚠️
pytorch_forecasting/models/xLSTMTime/xLSTMTime.py	0.00%	57 Missing ⚠️
...ytorch_forecasting/models/xLSTMTime/mLSTM/layer.py	0.00%	43 Missing ⚠️
...ytorch_forecasting/models/xLSTMTime/sLSTM/layer.py	0.00%	42 Missing ⚠️
...orch_forecasting/models/xLSTMTime/sLSTM/network.py	0.00%	20 Missing ⚠️
...orch_forecasting/models/xLSTMTime/mLSTM/network.py	0.00%	15 Missing ⚠️

Additional details and impacted files

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  Coverage        ?   84.37%           
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  Files           ?       40           
  Lines           ?     5144           
  Branches        ?        0           
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  Hits            ?     4340           
  Misses          ?      804           
  Partials        ?        0           

Flag	Coverage Δ
cpu	84.37% <0.00%> (?)
pytest	84.37% <0.00%> (?)

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[phoeenniixx]

hi @fkiraly, I am new to pytorch-forecasting and its tests and all, can you please tell me exactly what am I "missing"?

[phoeenniixx]

Will these tests suffice @fkiraly?