[ENH] EXPERIMENTAL: TFT model based on the new data pipeline

[phoeenniixx]

Description

This PR implements the tft model based on the new data pipeline. This PR is branched off from #1811

[codecov]

Codecov Report

❌ Patch coverage is 0% with 173 lines in your changes missing coverage. Please review.
⚠️ Please upload report for BASE (main@4c30351). Learn more about missing BASE report.

Files with missing lines	Patch %	Lines
...ting/models/temporal_fusion_transformer/_tft_v2.py	0.00%	97 Missing ⚠️
pytorch_forecasting/models/base/_base_model_v2.py	0.00%	76 Missing ⚠️

Additional details and impacted files

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Flag	Coverage Δ
cpu	84.20% <0.00%> (?)
pytest	84.20% <0.00%> (?)

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[fkiraly]

Yes maybe this will help some confused souls like mine :)

But you did everything right

[fkiraly]

Great!

May I just ask for minor changes:

• in the base model, include the warning message like in the data modules. Make a reference to self to also give hte user the name of the model
• make the new modules private
• I would suggest to use v2 as an abbreviation, i.e., _base_model_v2 and _tft_v2.

[phoeenniixx]

Hi @fkiraly, I think this PR is ready to merge