Add explainer/demo notebook

[al-jshen]

This is part of #6.

This adds a notebook to explain:

• the different components of the AION model (tokenizers, transformer model)
• how to load the different components
• how to prepare data for the model and how to tokenize
• how to do conditional sampling
• how to do embedding-based adaptation for a downstream task

Major pain point at the moment is the tokenizer loading, which is being worked on by @LTMeyer. I will update the notebook to use his new interface when it is ready.

[Copilot]

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aion/utils.py:4

• [nitpick] The function name 'to' is ambiguous; consider renaming it to a more descriptive name like 'move_to_device' to clarify its functionality.

def to(x, device='cuda'):

[EiffL]

@al-jshen can you check what the latest notebooks look like, and see if you can adapt yours to be complementary?

[al-jshen]

@al-jshen can you check what the latest notebooks look like, and see if you can adapt yours to be complementary?

Looks like this is outdated and is also basically replaced by the StellarTutorial.ipynb notebook.